5743 lines
221 KiB
Python
5743 lines
221 KiB
Python
# module pyparsing.py
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#
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# Copyright (c) 2003-2018 Paul T. McGuire
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#
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# Permission is hereby granted, free of charge, to any person obtaining
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# a copy of this software and associated documentation files (the
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# "Software"), to deal in the Software without restriction, including
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# without limitation the rights to use, copy, modify, merge, publish,
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# distribute, sublicense, and/or sell copies of the Software, and to
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# permit persons to whom the Software is furnished to do so, subject to
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# the following conditions:
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#
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# The above copyright notice and this permission notice shall be
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# included in all copies or substantial portions of the Software.
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#
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# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
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# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
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# IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
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# CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
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# TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
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# SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
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#
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__doc__ = \
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"""
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pyparsing module - Classes and methods to define and execute parsing grammars
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=============================================================================
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The pyparsing module is an alternative approach to creating and executing simple grammars,
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vs. the traditional lex/yacc approach, or the use of regular expressions. With pyparsing, you
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don't need to learn a new syntax for defining grammars or matching expressions - the parsing module
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provides a library of classes that you use to construct the grammar directly in Python.
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Here is a program to parse "Hello, World!" (or any greeting of the form
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C{"<salutation>, <addressee>!"}), built up using L{Word}, L{Literal}, and L{And} elements
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(L{'+'<ParserElement.__add__>} operator gives L{And} expressions, strings are auto-converted to
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L{Literal} expressions)::
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from pyparsing import Word, alphas
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# define grammar of a greeting
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greet = Word(alphas) + "," + Word(alphas) + "!"
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hello = "Hello, World!"
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print (hello, "->", greet.parseString(hello))
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The program outputs the following::
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Hello, World! -> ['Hello', ',', 'World', '!']
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The Python representation of the grammar is quite readable, owing to the self-explanatory
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class names, and the use of '+', '|' and '^' operators.
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The L{ParseResults} object returned from L{ParserElement.parseString<ParserElement.parseString>} can be accessed as a nested list, a dictionary, or an
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object with named attributes.
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The pyparsing module handles some of the problems that are typically vexing when writing text parsers:
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- extra or missing whitespace (the above program will also handle "Hello,World!", "Hello , World !", etc.)
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- quoted strings
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- embedded comments
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Getting Started -
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-----------------
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Visit the classes L{ParserElement} and L{ParseResults} to see the base classes that most other pyparsing
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classes inherit from. Use the docstrings for examples of how to:
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- construct literal match expressions from L{Literal} and L{CaselessLiteral} classes
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- construct character word-group expressions using the L{Word} class
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- see how to create repetitive expressions using L{ZeroOrMore} and L{OneOrMore} classes
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- use L{'+'<And>}, L{'|'<MatchFirst>}, L{'^'<Or>}, and L{'&'<Each>} operators to combine simple expressions into more complex ones
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- associate names with your parsed results using L{ParserElement.setResultsName}
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- find some helpful expression short-cuts like L{delimitedList} and L{oneOf}
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- find more useful common expressions in the L{pyparsing_common} namespace class
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"""
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__version__ = "2.2.1"
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__versionTime__ = "18 Sep 2018 00:49 UTC"
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__author__ = "Paul McGuire <ptmcg@users.sourceforge.net>"
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import string
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from weakref import ref as wkref
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import copy
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import sys
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import warnings
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import re
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import sre_constants
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import collections
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import pprint
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import traceback
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import types
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from datetime import datetime
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try:
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from _thread import RLock
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except ImportError:
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from threading import RLock
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try:
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# Python 3
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from collections.abc import Iterable
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from collections.abc import MutableMapping
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except ImportError:
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# Python 2.7
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from collections import Iterable
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from collections import MutableMapping
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try:
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from collections import OrderedDict as _OrderedDict
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except ImportError:
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try:
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from ordereddict import OrderedDict as _OrderedDict
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except ImportError:
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_OrderedDict = None
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#~ sys.stderr.write( "testing pyparsing module, version %s, %s\n" % (__version__,__versionTime__ ) )
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__all__ = [
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'And', 'CaselessKeyword', 'CaselessLiteral', 'CharsNotIn', 'Combine', 'Dict', 'Each', 'Empty',
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'FollowedBy', 'Forward', 'GoToColumn', 'Group', 'Keyword', 'LineEnd', 'LineStart', 'Literal',
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'MatchFirst', 'NoMatch', 'NotAny', 'OneOrMore', 'OnlyOnce', 'Optional', 'Or',
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'ParseBaseException', 'ParseElementEnhance', 'ParseException', 'ParseExpression', 'ParseFatalException',
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'ParseResults', 'ParseSyntaxException', 'ParserElement', 'QuotedString', 'RecursiveGrammarException',
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'Regex', 'SkipTo', 'StringEnd', 'StringStart', 'Suppress', 'Token', 'TokenConverter',
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'White', 'Word', 'WordEnd', 'WordStart', 'ZeroOrMore',
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'alphanums', 'alphas', 'alphas8bit', 'anyCloseTag', 'anyOpenTag', 'cStyleComment', 'col',
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'commaSeparatedList', 'commonHTMLEntity', 'countedArray', 'cppStyleComment', 'dblQuotedString',
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'dblSlashComment', 'delimitedList', 'dictOf', 'downcaseTokens', 'empty', 'hexnums',
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'htmlComment', 'javaStyleComment', 'line', 'lineEnd', 'lineStart', 'lineno',
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'makeHTMLTags', 'makeXMLTags', 'matchOnlyAtCol', 'matchPreviousExpr', 'matchPreviousLiteral',
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'nestedExpr', 'nullDebugAction', 'nums', 'oneOf', 'opAssoc', 'operatorPrecedence', 'printables',
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'punc8bit', 'pythonStyleComment', 'quotedString', 'removeQuotes', 'replaceHTMLEntity',
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'replaceWith', 'restOfLine', 'sglQuotedString', 'srange', 'stringEnd',
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'stringStart', 'traceParseAction', 'unicodeString', 'upcaseTokens', 'withAttribute',
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'indentedBlock', 'originalTextFor', 'ungroup', 'infixNotation','locatedExpr', 'withClass',
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'CloseMatch', 'tokenMap', 'pyparsing_common',
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]
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system_version = tuple(sys.version_info)[:3]
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PY_3 = system_version[0] == 3
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if PY_3:
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_MAX_INT = sys.maxsize
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basestring = str
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unichr = chr
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_ustr = str
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# build list of single arg builtins, that can be used as parse actions
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singleArgBuiltins = [sum, len, sorted, reversed, list, tuple, set, any, all, min, max]
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else:
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_MAX_INT = sys.maxint
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range = xrange
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def _ustr(obj):
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"""Drop-in replacement for str(obj) that tries to be Unicode friendly. It first tries
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str(obj). If that fails with a UnicodeEncodeError, then it tries unicode(obj). It
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then < returns the unicode object | encodes it with the default encoding | ... >.
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"""
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if isinstance(obj,unicode):
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return obj
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try:
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# If this works, then _ustr(obj) has the same behaviour as str(obj), so
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# it won't break any existing code.
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return str(obj)
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except UnicodeEncodeError:
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# Else encode it
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ret = unicode(obj).encode(sys.getdefaultencoding(), 'xmlcharrefreplace')
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xmlcharref = Regex(r'&#\d+;')
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xmlcharref.setParseAction(lambda t: '\\u' + hex(int(t[0][2:-1]))[2:])
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return xmlcharref.transformString(ret)
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# build list of single arg builtins, tolerant of Python version, that can be used as parse actions
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singleArgBuiltins = []
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import __builtin__
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for fname in "sum len sorted reversed list tuple set any all min max".split():
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try:
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singleArgBuiltins.append(getattr(__builtin__,fname))
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except AttributeError:
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continue
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_generatorType = type((y for y in range(1)))
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def _xml_escape(data):
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"""Escape &, <, >, ", ', etc. in a string of data."""
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# ampersand must be replaced first
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from_symbols = '&><"\''
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to_symbols = ('&'+s+';' for s in "amp gt lt quot apos".split())
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for from_,to_ in zip(from_symbols, to_symbols):
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data = data.replace(from_, to_)
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return data
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class _Constants(object):
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pass
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alphas = string.ascii_uppercase + string.ascii_lowercase
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nums = "0123456789"
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hexnums = nums + "ABCDEFabcdef"
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alphanums = alphas + nums
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_bslash = chr(92)
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printables = "".join(c for c in string.printable if c not in string.whitespace)
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class ParseBaseException(Exception):
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"""base exception class for all parsing runtime exceptions"""
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# Performance tuning: we construct a *lot* of these, so keep this
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# constructor as small and fast as possible
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def __init__( self, pstr, loc=0, msg=None, elem=None ):
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self.loc = loc
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if msg is None:
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self.msg = pstr
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self.pstr = ""
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else:
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self.msg = msg
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self.pstr = pstr
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self.parserElement = elem
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self.args = (pstr, loc, msg)
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@classmethod
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def _from_exception(cls, pe):
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"""
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internal factory method to simplify creating one type of ParseException
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from another - avoids having __init__ signature conflicts among subclasses
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"""
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return cls(pe.pstr, pe.loc, pe.msg, pe.parserElement)
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def __getattr__( self, aname ):
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"""supported attributes by name are:
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- lineno - returns the line number of the exception text
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- col - returns the column number of the exception text
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- line - returns the line containing the exception text
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"""
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if( aname == "lineno" ):
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return lineno( self.loc, self.pstr )
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elif( aname in ("col", "column") ):
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return col( self.loc, self.pstr )
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elif( aname == "line" ):
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return line( self.loc, self.pstr )
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else:
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raise AttributeError(aname)
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def __str__( self ):
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return "%s (at char %d), (line:%d, col:%d)" % \
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( self.msg, self.loc, self.lineno, self.column )
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def __repr__( self ):
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return _ustr(self)
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def markInputline( self, markerString = ">!<" ):
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"""Extracts the exception line from the input string, and marks
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the location of the exception with a special symbol.
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"""
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line_str = self.line
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line_column = self.column - 1
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if markerString:
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line_str = "".join((line_str[:line_column],
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markerString, line_str[line_column:]))
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return line_str.strip()
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def __dir__(self):
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return "lineno col line".split() + dir(type(self))
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class ParseException(ParseBaseException):
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"""
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Exception thrown when parse expressions don't match class;
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supported attributes by name are:
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- lineno - returns the line number of the exception text
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- col - returns the column number of the exception text
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- line - returns the line containing the exception text
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Example::
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try:
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Word(nums).setName("integer").parseString("ABC")
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except ParseException as pe:
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print(pe)
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print("column: {}".format(pe.col))
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prints::
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Expected integer (at char 0), (line:1, col:1)
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column: 1
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"""
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pass
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class ParseFatalException(ParseBaseException):
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"""user-throwable exception thrown when inconsistent parse content
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is found; stops all parsing immediately"""
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pass
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class ParseSyntaxException(ParseFatalException):
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"""just like L{ParseFatalException}, but thrown internally when an
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L{ErrorStop<And._ErrorStop>} ('-' operator) indicates that parsing is to stop
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immediately because an unbacktrackable syntax error has been found"""
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pass
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#~ class ReparseException(ParseBaseException):
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#~ """Experimental class - parse actions can raise this exception to cause
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#~ pyparsing to reparse the input string:
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#~ - with a modified input string, and/or
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#~ - with a modified start location
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#~ Set the values of the ReparseException in the constructor, and raise the
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#~ exception in a parse action to cause pyparsing to use the new string/location.
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#~ Setting the values as None causes no change to be made.
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#~ """
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#~ def __init_( self, newstring, restartLoc ):
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#~ self.newParseText = newstring
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#~ self.reparseLoc = restartLoc
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class RecursiveGrammarException(Exception):
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"""exception thrown by L{ParserElement.validate} if the grammar could be improperly recursive"""
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def __init__( self, parseElementList ):
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self.parseElementTrace = parseElementList
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def __str__( self ):
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return "RecursiveGrammarException: %s" % self.parseElementTrace
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class _ParseResultsWithOffset(object):
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def __init__(self,p1,p2):
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self.tup = (p1,p2)
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def __getitem__(self,i):
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return self.tup[i]
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def __repr__(self):
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return repr(self.tup[0])
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def setOffset(self,i):
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self.tup = (self.tup[0],i)
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class ParseResults(object):
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"""
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Structured parse results, to provide multiple means of access to the parsed data:
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- as a list (C{len(results)})
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- by list index (C{results[0], results[1]}, etc.)
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- by attribute (C{results.<resultsName>} - see L{ParserElement.setResultsName})
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Example::
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integer = Word(nums)
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date_str = (integer.setResultsName("year") + '/'
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+ integer.setResultsName("month") + '/'
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+ integer.setResultsName("day"))
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# equivalent form:
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# date_str = integer("year") + '/' + integer("month") + '/' + integer("day")
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# parseString returns a ParseResults object
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result = date_str.parseString("1999/12/31")
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def test(s, fn=repr):
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print("%s -> %s" % (s, fn(eval(s))))
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test("list(result)")
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test("result[0]")
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test("result['month']")
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test("result.day")
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test("'month' in result")
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test("'minutes' in result")
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test("result.dump()", str)
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prints::
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list(result) -> ['1999', '/', '12', '/', '31']
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result[0] -> '1999'
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result['month'] -> '12'
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result.day -> '31'
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'month' in result -> True
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'minutes' in result -> False
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result.dump() -> ['1999', '/', '12', '/', '31']
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- day: 31
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- month: 12
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- year: 1999
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"""
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def __new__(cls, toklist=None, name=None, asList=True, modal=True ):
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if isinstance(toklist, cls):
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return toklist
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retobj = object.__new__(cls)
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retobj.__doinit = True
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return retobj
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# Performance tuning: we construct a *lot* of these, so keep this
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# constructor as small and fast as possible
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def __init__( self, toklist=None, name=None, asList=True, modal=True, isinstance=isinstance ):
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if self.__doinit:
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self.__doinit = False
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self.__name = None
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self.__parent = None
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self.__accumNames = {}
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self.__asList = asList
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self.__modal = modal
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if toklist is None:
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toklist = []
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if isinstance(toklist, list):
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self.__toklist = toklist[:]
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elif isinstance(toklist, _generatorType):
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self.__toklist = list(toklist)
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else:
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self.__toklist = [toklist]
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self.__tokdict = dict()
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if name is not None and name:
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if not modal:
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self.__accumNames[name] = 0
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if isinstance(name,int):
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name = _ustr(name) # will always return a str, but use _ustr for consistency
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self.__name = name
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if not (isinstance(toklist, (type(None), basestring, list)) and toklist in (None,'',[])):
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if isinstance(toklist,basestring):
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toklist = [ toklist ]
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if asList:
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if isinstance(toklist,ParseResults):
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self[name] = _ParseResultsWithOffset(toklist.copy(),0)
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else:
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self[name] = _ParseResultsWithOffset(ParseResults(toklist[0]),0)
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self[name].__name = name
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else:
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try:
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self[name] = toklist[0]
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except (KeyError,TypeError,IndexError):
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self[name] = toklist
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|
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def __getitem__( self, i ):
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if isinstance( i, (int,slice) ):
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return self.__toklist[i]
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else:
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if i not in self.__accumNames:
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return self.__tokdict[i][-1][0]
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else:
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return ParseResults([ v[0] for v in self.__tokdict[i] ])
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|
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def __setitem__( self, k, v, isinstance=isinstance ):
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if isinstance(v,_ParseResultsWithOffset):
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self.__tokdict[k] = self.__tokdict.get(k,list()) + [v]
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sub = v[0]
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elif isinstance(k,(int,slice)):
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self.__toklist[k] = v
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sub = v
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else:
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self.__tokdict[k] = self.__tokdict.get(k,list()) + [_ParseResultsWithOffset(v,0)]
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sub = v
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if isinstance(sub,ParseResults):
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sub.__parent = wkref(self)
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|
|
|
def __delitem__( self, i ):
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if isinstance(i,(int,slice)):
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mylen = len( self.__toklist )
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del self.__toklist[i]
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|
|
|
# convert int to slice
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|
if isinstance(i, int):
|
|
if i < 0:
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i += mylen
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i = slice(i, i+1)
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|
# get removed indices
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removed = list(range(*i.indices(mylen)))
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removed.reverse()
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# fixup indices in token dictionary
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for name,occurrences in self.__tokdict.items():
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|
for j in removed:
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for k, (value, position) in enumerate(occurrences):
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occurrences[k] = _ParseResultsWithOffset(value, position - (position > j))
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|
else:
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del self.__tokdict[i]
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|
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def __contains__( self, k ):
|
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return k in self.__tokdict
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|
|
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def __len__( self ): return len( self.__toklist )
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|
def __bool__(self): return ( not not self.__toklist )
|
|
__nonzero__ = __bool__
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|
def __iter__( self ): return iter( self.__toklist )
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|
def __reversed__( self ): return iter( self.__toklist[::-1] )
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|
def _iterkeys( self ):
|
|
if hasattr(self.__tokdict, "iterkeys"):
|
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return self.__tokdict.iterkeys()
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else:
|
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return iter(self.__tokdict)
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|
|
|
def _itervalues( self ):
|
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return (self[k] for k in self._iterkeys())
|
|
|
|
def _iteritems( self ):
|
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return ((k, self[k]) for k in self._iterkeys())
|
|
|
|
if PY_3:
|
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keys = _iterkeys
|
|
"""Returns an iterator of all named result keys (Python 3.x only)."""
|
|
|
|
values = _itervalues
|
|
"""Returns an iterator of all named result values (Python 3.x only)."""
|
|
|
|
items = _iteritems
|
|
"""Returns an iterator of all named result key-value tuples (Python 3.x only)."""
|
|
|
|
else:
|
|
iterkeys = _iterkeys
|
|
"""Returns an iterator of all named result keys (Python 2.x only)."""
|
|
|
|
itervalues = _itervalues
|
|
"""Returns an iterator of all named result values (Python 2.x only)."""
|
|
|
|
iteritems = _iteritems
|
|
"""Returns an iterator of all named result key-value tuples (Python 2.x only)."""
|
|
|
|
def keys( self ):
|
|
"""Returns all named result keys (as a list in Python 2.x, as an iterator in Python 3.x)."""
|
|
return list(self.iterkeys())
|
|
|
|
def values( self ):
|
|
"""Returns all named result values (as a list in Python 2.x, as an iterator in Python 3.x)."""
|
|
return list(self.itervalues())
|
|
|
|
def items( self ):
|
|
"""Returns all named result key-values (as a list of tuples in Python 2.x, as an iterator in Python 3.x)."""
|
|
return list(self.iteritems())
|
|
|
|
def haskeys( self ):
|
|
"""Since keys() returns an iterator, this method is helpful in bypassing
|
|
code that looks for the existence of any defined results names."""
|
|
return bool(self.__tokdict)
|
|
|
|
def pop( self, *args, **kwargs):
|
|
"""
|
|
Removes and returns item at specified index (default=C{last}).
|
|
Supports both C{list} and C{dict} semantics for C{pop()}. If passed no
|
|
argument or an integer argument, it will use C{list} semantics
|
|
and pop tokens from the list of parsed tokens. If passed a
|
|
non-integer argument (most likely a string), it will use C{dict}
|
|
semantics and pop the corresponding value from any defined
|
|
results names. A second default return value argument is
|
|
supported, just as in C{dict.pop()}.
|
|
|
|
Example::
|
|
def remove_first(tokens):
|
|
tokens.pop(0)
|
|
print(OneOrMore(Word(nums)).parseString("0 123 321")) # -> ['0', '123', '321']
|
|
print(OneOrMore(Word(nums)).addParseAction(remove_first).parseString("0 123 321")) # -> ['123', '321']
|
|
|
|
label = Word(alphas)
|
|
patt = label("LABEL") + OneOrMore(Word(nums))
|
|
print(patt.parseString("AAB 123 321").dump())
|
|
|
|
# Use pop() in a parse action to remove named result (note that corresponding value is not
|
|
# removed from list form of results)
|
|
def remove_LABEL(tokens):
|
|
tokens.pop("LABEL")
|
|
return tokens
|
|
patt.addParseAction(remove_LABEL)
|
|
print(patt.parseString("AAB 123 321").dump())
|
|
prints::
|
|
['AAB', '123', '321']
|
|
- LABEL: AAB
|
|
|
|
['AAB', '123', '321']
|
|
"""
|
|
if not args:
|
|
args = [-1]
|
|
for k,v in kwargs.items():
|
|
if k == 'default':
|
|
args = (args[0], v)
|
|
else:
|
|
raise TypeError("pop() got an unexpected keyword argument '%s'" % k)
|
|
if (isinstance(args[0], int) or
|
|
len(args) == 1 or
|
|
args[0] in self):
|
|
index = args[0]
|
|
ret = self[index]
|
|
del self[index]
|
|
return ret
|
|
else:
|
|
defaultvalue = args[1]
|
|
return defaultvalue
|
|
|
|
def get(self, key, defaultValue=None):
|
|
"""
|
|
Returns named result matching the given key, or if there is no
|
|
such name, then returns the given C{defaultValue} or C{None} if no
|
|
C{defaultValue} is specified.
|
|
|
|
Similar to C{dict.get()}.
|
|
|
|
Example::
|
|
integer = Word(nums)
|
|
date_str = integer("year") + '/' + integer("month") + '/' + integer("day")
|
|
|
|
result = date_str.parseString("1999/12/31")
|
|
print(result.get("year")) # -> '1999'
|
|
print(result.get("hour", "not specified")) # -> 'not specified'
|
|
print(result.get("hour")) # -> None
|
|
"""
|
|
if key in self:
|
|
return self[key]
|
|
else:
|
|
return defaultValue
|
|
|
|
def insert( self, index, insStr ):
|
|
"""
|
|
Inserts new element at location index in the list of parsed tokens.
|
|
|
|
Similar to C{list.insert()}.
|
|
|
|
Example::
|
|
print(OneOrMore(Word(nums)).parseString("0 123 321")) # -> ['0', '123', '321']
|
|
|
|
# use a parse action to insert the parse location in the front of the parsed results
|
|
def insert_locn(locn, tokens):
|
|
tokens.insert(0, locn)
|
|
print(OneOrMore(Word(nums)).addParseAction(insert_locn).parseString("0 123 321")) # -> [0, '0', '123', '321']
|
|
"""
|
|
self.__toklist.insert(index, insStr)
|
|
# fixup indices in token dictionary
|
|
for name,occurrences in self.__tokdict.items():
|
|
for k, (value, position) in enumerate(occurrences):
|
|
occurrences[k] = _ParseResultsWithOffset(value, position + (position > index))
|
|
|
|
def append( self, item ):
|
|
"""
|
|
Add single element to end of ParseResults list of elements.
|
|
|
|
Example::
|
|
print(OneOrMore(Word(nums)).parseString("0 123 321")) # -> ['0', '123', '321']
|
|
|
|
# use a parse action to compute the sum of the parsed integers, and add it to the end
|
|
def append_sum(tokens):
|
|
tokens.append(sum(map(int, tokens)))
|
|
print(OneOrMore(Word(nums)).addParseAction(append_sum).parseString("0 123 321")) # -> ['0', '123', '321', 444]
|
|
"""
|
|
self.__toklist.append(item)
|
|
|
|
def extend( self, itemseq ):
|
|
"""
|
|
Add sequence of elements to end of ParseResults list of elements.
|
|
|
|
Example::
|
|
patt = OneOrMore(Word(alphas))
|
|
|
|
# use a parse action to append the reverse of the matched strings, to make a palindrome
|
|
def make_palindrome(tokens):
|
|
tokens.extend(reversed([t[::-1] for t in tokens]))
|
|
return ''.join(tokens)
|
|
print(patt.addParseAction(make_palindrome).parseString("lskdj sdlkjf lksd")) # -> 'lskdjsdlkjflksddsklfjkldsjdksl'
|
|
"""
|
|
if isinstance(itemseq, ParseResults):
|
|
self += itemseq
|
|
else:
|
|
self.__toklist.extend(itemseq)
|
|
|
|
def clear( self ):
|
|
"""
|
|
Clear all elements and results names.
|
|
"""
|
|
del self.__toklist[:]
|
|
self.__tokdict.clear()
|
|
|
|
def __getattr__( self, name ):
|
|
try:
|
|
return self[name]
|
|
except KeyError:
|
|
return ""
|
|
|
|
if name in self.__tokdict:
|
|
if name not in self.__accumNames:
|
|
return self.__tokdict[name][-1][0]
|
|
else:
|
|
return ParseResults([ v[0] for v in self.__tokdict[name] ])
|
|
else:
|
|
return ""
|
|
|
|
def __add__( self, other ):
|
|
ret = self.copy()
|
|
ret += other
|
|
return ret
|
|
|
|
def __iadd__( self, other ):
|
|
if other.__tokdict:
|
|
offset = len(self.__toklist)
|
|
addoffset = lambda a: offset if a<0 else a+offset
|
|
otheritems = other.__tokdict.items()
|
|
otherdictitems = [(k, _ParseResultsWithOffset(v[0],addoffset(v[1])) )
|
|
for (k,vlist) in otheritems for v in vlist]
|
|
for k,v in otherdictitems:
|
|
self[k] = v
|
|
if isinstance(v[0],ParseResults):
|
|
v[0].__parent = wkref(self)
|
|
|
|
self.__toklist += other.__toklist
|
|
self.__accumNames.update( other.__accumNames )
|
|
return self
|
|
|
|
def __radd__(self, other):
|
|
if isinstance(other,int) and other == 0:
|
|
# useful for merging many ParseResults using sum() builtin
|
|
return self.copy()
|
|
else:
|
|
# this may raise a TypeError - so be it
|
|
return other + self
|
|
|
|
def __repr__( self ):
|
|
return "(%s, %s)" % ( repr( self.__toklist ), repr( self.__tokdict ) )
|
|
|
|
def __str__( self ):
|
|
return '[' + ', '.join(_ustr(i) if isinstance(i, ParseResults) else repr(i) for i in self.__toklist) + ']'
|
|
|
|
def _asStringList( self, sep='' ):
|
|
out = []
|
|
for item in self.__toklist:
|
|
if out and sep:
|
|
out.append(sep)
|
|
if isinstance( item, ParseResults ):
|
|
out += item._asStringList()
|
|
else:
|
|
out.append( _ustr(item) )
|
|
return out
|
|
|
|
def asList( self ):
|
|
"""
|
|
Returns the parse results as a nested list of matching tokens, all converted to strings.
|
|
|
|
Example::
|
|
patt = OneOrMore(Word(alphas))
|
|
result = patt.parseString("sldkj lsdkj sldkj")
|
|
# even though the result prints in string-like form, it is actually a pyparsing ParseResults
|
|
print(type(result), result) # -> <class 'pyparsing.ParseResults'> ['sldkj', 'lsdkj', 'sldkj']
|
|
|
|
# Use asList() to create an actual list
|
|
result_list = result.asList()
|
|
print(type(result_list), result_list) # -> <class 'list'> ['sldkj', 'lsdkj', 'sldkj']
|
|
"""
|
|
return [res.asList() if isinstance(res,ParseResults) else res for res in self.__toklist]
|
|
|
|
def asDict( self ):
|
|
"""
|
|
Returns the named parse results as a nested dictionary.
|
|
|
|
Example::
|
|
integer = Word(nums)
|
|
date_str = integer("year") + '/' + integer("month") + '/' + integer("day")
|
|
|
|
result = date_str.parseString('12/31/1999')
|
|
print(type(result), repr(result)) # -> <class 'pyparsing.ParseResults'> (['12', '/', '31', '/', '1999'], {'day': [('1999', 4)], 'year': [('12', 0)], 'month': [('31', 2)]})
|
|
|
|
result_dict = result.asDict()
|
|
print(type(result_dict), repr(result_dict)) # -> <class 'dict'> {'day': '1999', 'year': '12', 'month': '31'}
|
|
|
|
# even though a ParseResults supports dict-like access, sometime you just need to have a dict
|
|
import json
|
|
print(json.dumps(result)) # -> Exception: TypeError: ... is not JSON serializable
|
|
print(json.dumps(result.asDict())) # -> {"month": "31", "day": "1999", "year": "12"}
|
|
"""
|
|
if PY_3:
|
|
item_fn = self.items
|
|
else:
|
|
item_fn = self.iteritems
|
|
|
|
def toItem(obj):
|
|
if isinstance(obj, ParseResults):
|
|
if obj.haskeys():
|
|
return obj.asDict()
|
|
else:
|
|
return [toItem(v) for v in obj]
|
|
else:
|
|
return obj
|
|
|
|
return dict((k,toItem(v)) for k,v in item_fn())
|
|
|
|
def copy( self ):
|
|
"""
|
|
Returns a new copy of a C{ParseResults} object.
|
|
"""
|
|
ret = ParseResults( self.__toklist )
|
|
ret.__tokdict = self.__tokdict.copy()
|
|
ret.__parent = self.__parent
|
|
ret.__accumNames.update( self.__accumNames )
|
|
ret.__name = self.__name
|
|
return ret
|
|
|
|
def asXML( self, doctag=None, namedItemsOnly=False, indent="", formatted=True ):
|
|
"""
|
|
(Deprecated) Returns the parse results as XML. Tags are created for tokens and lists that have defined results names.
|
|
"""
|
|
nl = "\n"
|
|
out = []
|
|
namedItems = dict((v[1],k) for (k,vlist) in self.__tokdict.items()
|
|
for v in vlist)
|
|
nextLevelIndent = indent + " "
|
|
|
|
# collapse out indents if formatting is not desired
|
|
if not formatted:
|
|
indent = ""
|
|
nextLevelIndent = ""
|
|
nl = ""
|
|
|
|
selfTag = None
|
|
if doctag is not None:
|
|
selfTag = doctag
|
|
else:
|
|
if self.__name:
|
|
selfTag = self.__name
|
|
|
|
if not selfTag:
|
|
if namedItemsOnly:
|
|
return ""
|
|
else:
|
|
selfTag = "ITEM"
|
|
|
|
out += [ nl, indent, "<", selfTag, ">" ]
|
|
|
|
for i,res in enumerate(self.__toklist):
|
|
if isinstance(res,ParseResults):
|
|
if i in namedItems:
|
|
out += [ res.asXML(namedItems[i],
|
|
namedItemsOnly and doctag is None,
|
|
nextLevelIndent,
|
|
formatted)]
|
|
else:
|
|
out += [ res.asXML(None,
|
|
namedItemsOnly and doctag is None,
|
|
nextLevelIndent,
|
|
formatted)]
|
|
else:
|
|
# individual token, see if there is a name for it
|
|
resTag = None
|
|
if i in namedItems:
|
|
resTag = namedItems[i]
|
|
if not resTag:
|
|
if namedItemsOnly:
|
|
continue
|
|
else:
|
|
resTag = "ITEM"
|
|
xmlBodyText = _xml_escape(_ustr(res))
|
|
out += [ nl, nextLevelIndent, "<", resTag, ">",
|
|
xmlBodyText,
|
|
"</", resTag, ">" ]
|
|
|
|
out += [ nl, indent, "</", selfTag, ">" ]
|
|
return "".join(out)
|
|
|
|
def __lookup(self,sub):
|
|
for k,vlist in self.__tokdict.items():
|
|
for v,loc in vlist:
|
|
if sub is v:
|
|
return k
|
|
return None
|
|
|
|
def getName(self):
|
|
r"""
|
|
Returns the results name for this token expression. Useful when several
|
|
different expressions might match at a particular location.
|
|
|
|
Example::
|
|
integer = Word(nums)
|
|
ssn_expr = Regex(r"\d\d\d-\d\d-\d\d\d\d")
|
|
house_number_expr = Suppress('#') + Word(nums, alphanums)
|
|
user_data = (Group(house_number_expr)("house_number")
|
|
| Group(ssn_expr)("ssn")
|
|
| Group(integer)("age"))
|
|
user_info = OneOrMore(user_data)
|
|
|
|
result = user_info.parseString("22 111-22-3333 #221B")
|
|
for item in result:
|
|
print(item.getName(), ':', item[0])
|
|
prints::
|
|
age : 22
|
|
ssn : 111-22-3333
|
|
house_number : 221B
|
|
"""
|
|
if self.__name:
|
|
return self.__name
|
|
elif self.__parent:
|
|
par = self.__parent()
|
|
if par:
|
|
return par.__lookup(self)
|
|
else:
|
|
return None
|
|
elif (len(self) == 1 and
|
|
len(self.__tokdict) == 1 and
|
|
next(iter(self.__tokdict.values()))[0][1] in (0,-1)):
|
|
return next(iter(self.__tokdict.keys()))
|
|
else:
|
|
return None
|
|
|
|
def dump(self, indent='', depth=0, full=True):
|
|
"""
|
|
Diagnostic method for listing out the contents of a C{ParseResults}.
|
|
Accepts an optional C{indent} argument so that this string can be embedded
|
|
in a nested display of other data.
|
|
|
|
Example::
|
|
integer = Word(nums)
|
|
date_str = integer("year") + '/' + integer("month") + '/' + integer("day")
|
|
|
|
result = date_str.parseString('12/31/1999')
|
|
print(result.dump())
|
|
prints::
|
|
['12', '/', '31', '/', '1999']
|
|
- day: 1999
|
|
- month: 31
|
|
- year: 12
|
|
"""
|
|
out = []
|
|
NL = '\n'
|
|
out.append( indent+_ustr(self.asList()) )
|
|
if full:
|
|
if self.haskeys():
|
|
items = sorted((str(k), v) for k,v in self.items())
|
|
for k,v in items:
|
|
if out:
|
|
out.append(NL)
|
|
out.append( "%s%s- %s: " % (indent,(' '*depth), k) )
|
|
if isinstance(v,ParseResults):
|
|
if v:
|
|
out.append( v.dump(indent,depth+1) )
|
|
else:
|
|
out.append(_ustr(v))
|
|
else:
|
|
out.append(repr(v))
|
|
elif any(isinstance(vv,ParseResults) for vv in self):
|
|
v = self
|
|
for i,vv in enumerate(v):
|
|
if isinstance(vv,ParseResults):
|
|
out.append("\n%s%s[%d]:\n%s%s%s" % (indent,(' '*(depth)),i,indent,(' '*(depth+1)),vv.dump(indent,depth+1) ))
|
|
else:
|
|
out.append("\n%s%s[%d]:\n%s%s%s" % (indent,(' '*(depth)),i,indent,(' '*(depth+1)),_ustr(vv)))
|
|
|
|
return "".join(out)
|
|
|
|
def pprint(self, *args, **kwargs):
|
|
"""
|
|
Pretty-printer for parsed results as a list, using the C{pprint} module.
|
|
Accepts additional positional or keyword args as defined for the
|
|
C{pprint.pprint} method. (U{http://docs.python.org/3/library/pprint.html#pprint.pprint})
|
|
|
|
Example::
|
|
ident = Word(alphas, alphanums)
|
|
num = Word(nums)
|
|
func = Forward()
|
|
term = ident | num | Group('(' + func + ')')
|
|
func <<= ident + Group(Optional(delimitedList(term)))
|
|
result = func.parseString("fna a,b,(fnb c,d,200),100")
|
|
result.pprint(width=40)
|
|
prints::
|
|
['fna',
|
|
['a',
|
|
'b',
|
|
['(', 'fnb', ['c', 'd', '200'], ')'],
|
|
'100']]
|
|
"""
|
|
pprint.pprint(self.asList(), *args, **kwargs)
|
|
|
|
# add support for pickle protocol
|
|
def __getstate__(self):
|
|
return ( self.__toklist,
|
|
( self.__tokdict.copy(),
|
|
self.__parent is not None and self.__parent() or None,
|
|
self.__accumNames,
|
|
self.__name ) )
|
|
|
|
def __setstate__(self,state):
|
|
self.__toklist = state[0]
|
|
(self.__tokdict,
|
|
par,
|
|
inAccumNames,
|
|
self.__name) = state[1]
|
|
self.__accumNames = {}
|
|
self.__accumNames.update(inAccumNames)
|
|
if par is not None:
|
|
self.__parent = wkref(par)
|
|
else:
|
|
self.__parent = None
|
|
|
|
def __getnewargs__(self):
|
|
return self.__toklist, self.__name, self.__asList, self.__modal
|
|
|
|
def __dir__(self):
|
|
return (dir(type(self)) + list(self.keys()))
|
|
|
|
MutableMapping.register(ParseResults)
|
|
|
|
def col (loc,strg):
|
|
"""Returns current column within a string, counting newlines as line separators.
|
|
The first column is number 1.
|
|
|
|
Note: the default parsing behavior is to expand tabs in the input string
|
|
before starting the parsing process. See L{I{ParserElement.parseString}<ParserElement.parseString>} for more information
|
|
on parsing strings containing C{<TAB>}s, and suggested methods to maintain a
|
|
consistent view of the parsed string, the parse location, and line and column
|
|
positions within the parsed string.
|
|
"""
|
|
s = strg
|
|
return 1 if 0<loc<len(s) and s[loc-1] == '\n' else loc - s.rfind("\n", 0, loc)
|
|
|
|
def lineno(loc,strg):
|
|
"""Returns current line number within a string, counting newlines as line separators.
|
|
The first line is number 1.
|
|
|
|
Note: the default parsing behavior is to expand tabs in the input string
|
|
before starting the parsing process. See L{I{ParserElement.parseString}<ParserElement.parseString>} for more information
|
|
on parsing strings containing C{<TAB>}s, and suggested methods to maintain a
|
|
consistent view of the parsed string, the parse location, and line and column
|
|
positions within the parsed string.
|
|
"""
|
|
return strg.count("\n",0,loc) + 1
|
|
|
|
def line( loc, strg ):
|
|
"""Returns the line of text containing loc within a string, counting newlines as line separators.
|
|
"""
|
|
lastCR = strg.rfind("\n", 0, loc)
|
|
nextCR = strg.find("\n", loc)
|
|
if nextCR >= 0:
|
|
return strg[lastCR+1:nextCR]
|
|
else:
|
|
return strg[lastCR+1:]
|
|
|
|
def _defaultStartDebugAction( instring, loc, expr ):
|
|
print (("Match " + _ustr(expr) + " at loc " + _ustr(loc) + "(%d,%d)" % ( lineno(loc,instring), col(loc,instring) )))
|
|
|
|
def _defaultSuccessDebugAction( instring, startloc, endloc, expr, toks ):
|
|
print ("Matched " + _ustr(expr) + " -> " + str(toks.asList()))
|
|
|
|
def _defaultExceptionDebugAction( instring, loc, expr, exc ):
|
|
print ("Exception raised:" + _ustr(exc))
|
|
|
|
def nullDebugAction(*args):
|
|
"""'Do-nothing' debug action, to suppress debugging output during parsing."""
|
|
pass
|
|
|
|
# Only works on Python 3.x - nonlocal is toxic to Python 2 installs
|
|
#~ 'decorator to trim function calls to match the arity of the target'
|
|
#~ def _trim_arity(func, maxargs=3):
|
|
#~ if func in singleArgBuiltins:
|
|
#~ return lambda s,l,t: func(t)
|
|
#~ limit = 0
|
|
#~ foundArity = False
|
|
#~ def wrapper(*args):
|
|
#~ nonlocal limit,foundArity
|
|
#~ while 1:
|
|
#~ try:
|
|
#~ ret = func(*args[limit:])
|
|
#~ foundArity = True
|
|
#~ return ret
|
|
#~ except TypeError:
|
|
#~ if limit == maxargs or foundArity:
|
|
#~ raise
|
|
#~ limit += 1
|
|
#~ continue
|
|
#~ return wrapper
|
|
|
|
# this version is Python 2.x-3.x cross-compatible
|
|
'decorator to trim function calls to match the arity of the target'
|
|
def _trim_arity(func, maxargs=2):
|
|
if func in singleArgBuiltins:
|
|
return lambda s,l,t: func(t)
|
|
limit = [0]
|
|
foundArity = [False]
|
|
|
|
# traceback return data structure changed in Py3.5 - normalize back to plain tuples
|
|
if system_version[:2] >= (3,5):
|
|
def extract_stack(limit=0):
|
|
# special handling for Python 3.5.0 - extra deep call stack by 1
|
|
offset = -3 if system_version == (3,5,0) else -2
|
|
frame_summary = traceback.extract_stack(limit=-offset+limit-1)[offset]
|
|
return [frame_summary[:2]]
|
|
def extract_tb(tb, limit=0):
|
|
frames = traceback.extract_tb(tb, limit=limit)
|
|
frame_summary = frames[-1]
|
|
return [frame_summary[:2]]
|
|
else:
|
|
extract_stack = traceback.extract_stack
|
|
extract_tb = traceback.extract_tb
|
|
|
|
# synthesize what would be returned by traceback.extract_stack at the call to
|
|
# user's parse action 'func', so that we don't incur call penalty at parse time
|
|
|
|
LINE_DIFF = 6
|
|
# IF ANY CODE CHANGES, EVEN JUST COMMENTS OR BLANK LINES, BETWEEN THE NEXT LINE AND
|
|
# THE CALL TO FUNC INSIDE WRAPPER, LINE_DIFF MUST BE MODIFIED!!!!
|
|
this_line = extract_stack(limit=2)[-1]
|
|
pa_call_line_synth = (this_line[0], this_line[1]+LINE_DIFF)
|
|
|
|
def wrapper(*args):
|
|
while 1:
|
|
try:
|
|
ret = func(*args[limit[0]:])
|
|
foundArity[0] = True
|
|
return ret
|
|
except TypeError:
|
|
# re-raise TypeErrors if they did not come from our arity testing
|
|
if foundArity[0]:
|
|
raise
|
|
else:
|
|
try:
|
|
tb = sys.exc_info()[-1]
|
|
if not extract_tb(tb, limit=2)[-1][:2] == pa_call_line_synth:
|
|
raise
|
|
finally:
|
|
del tb
|
|
|
|
if limit[0] <= maxargs:
|
|
limit[0] += 1
|
|
continue
|
|
raise
|
|
|
|
# copy func name to wrapper for sensible debug output
|
|
func_name = "<parse action>"
|
|
try:
|
|
func_name = getattr(func, '__name__',
|
|
getattr(func, '__class__').__name__)
|
|
except Exception:
|
|
func_name = str(func)
|
|
wrapper.__name__ = func_name
|
|
|
|
return wrapper
|
|
|
|
class ParserElement(object):
|
|
"""Abstract base level parser element class."""
|
|
DEFAULT_WHITE_CHARS = " \n\t\r"
|
|
verbose_stacktrace = False
|
|
|
|
@staticmethod
|
|
def setDefaultWhitespaceChars( chars ):
|
|
r"""
|
|
Overrides the default whitespace chars
|
|
|
|
Example::
|
|
# default whitespace chars are space, <TAB> and newline
|
|
OneOrMore(Word(alphas)).parseString("abc def\nghi jkl") # -> ['abc', 'def', 'ghi', 'jkl']
|
|
|
|
# change to just treat newline as significant
|
|
ParserElement.setDefaultWhitespaceChars(" \t")
|
|
OneOrMore(Word(alphas)).parseString("abc def\nghi jkl") # -> ['abc', 'def']
|
|
"""
|
|
ParserElement.DEFAULT_WHITE_CHARS = chars
|
|
|
|
@staticmethod
|
|
def inlineLiteralsUsing(cls):
|
|
"""
|
|
Set class to be used for inclusion of string literals into a parser.
|
|
|
|
Example::
|
|
# default literal class used is Literal
|
|
integer = Word(nums)
|
|
date_str = integer("year") + '/' + integer("month") + '/' + integer("day")
|
|
|
|
date_str.parseString("1999/12/31") # -> ['1999', '/', '12', '/', '31']
|
|
|
|
|
|
# change to Suppress
|
|
ParserElement.inlineLiteralsUsing(Suppress)
|
|
date_str = integer("year") + '/' + integer("month") + '/' + integer("day")
|
|
|
|
date_str.parseString("1999/12/31") # -> ['1999', '12', '31']
|
|
"""
|
|
ParserElement._literalStringClass = cls
|
|
|
|
def __init__( self, savelist=False ):
|
|
self.parseAction = list()
|
|
self.failAction = None
|
|
#~ self.name = "<unknown>" # don't define self.name, let subclasses try/except upcall
|
|
self.strRepr = None
|
|
self.resultsName = None
|
|
self.saveAsList = savelist
|
|
self.skipWhitespace = True
|
|
self.whiteChars = ParserElement.DEFAULT_WHITE_CHARS
|
|
self.copyDefaultWhiteChars = True
|
|
self.mayReturnEmpty = False # used when checking for left-recursion
|
|
self.keepTabs = False
|
|
self.ignoreExprs = list()
|
|
self.debug = False
|
|
self.streamlined = False
|
|
self.mayIndexError = True # used to optimize exception handling for subclasses that don't advance parse index
|
|
self.errmsg = ""
|
|
self.modalResults = True # used to mark results names as modal (report only last) or cumulative (list all)
|
|
self.debugActions = ( None, None, None ) #custom debug actions
|
|
self.re = None
|
|
self.callPreparse = True # used to avoid redundant calls to preParse
|
|
self.callDuringTry = False
|
|
|
|
def copy( self ):
|
|
"""
|
|
Make a copy of this C{ParserElement}. Useful for defining different parse actions
|
|
for the same parsing pattern, using copies of the original parse element.
|
|
|
|
Example::
|
|
integer = Word(nums).setParseAction(lambda toks: int(toks[0]))
|
|
integerK = integer.copy().addParseAction(lambda toks: toks[0]*1024) + Suppress("K")
|
|
integerM = integer.copy().addParseAction(lambda toks: toks[0]*1024*1024) + Suppress("M")
|
|
|
|
print(OneOrMore(integerK | integerM | integer).parseString("5K 100 640K 256M"))
|
|
prints::
|
|
[5120, 100, 655360, 268435456]
|
|
Equivalent form of C{expr.copy()} is just C{expr()}::
|
|
integerM = integer().addParseAction(lambda toks: toks[0]*1024*1024) + Suppress("M")
|
|
"""
|
|
cpy = copy.copy( self )
|
|
cpy.parseAction = self.parseAction[:]
|
|
cpy.ignoreExprs = self.ignoreExprs[:]
|
|
if self.copyDefaultWhiteChars:
|
|
cpy.whiteChars = ParserElement.DEFAULT_WHITE_CHARS
|
|
return cpy
|
|
|
|
def setName( self, name ):
|
|
"""
|
|
Define name for this expression, makes debugging and exception messages clearer.
|
|
|
|
Example::
|
|
Word(nums).parseString("ABC") # -> Exception: Expected W:(0123...) (at char 0), (line:1, col:1)
|
|
Word(nums).setName("integer").parseString("ABC") # -> Exception: Expected integer (at char 0), (line:1, col:1)
|
|
"""
|
|
self.name = name
|
|
self.errmsg = "Expected " + self.name
|
|
if hasattr(self,"exception"):
|
|
self.exception.msg = self.errmsg
|
|
return self
|
|
|
|
def setResultsName( self, name, listAllMatches=False ):
|
|
"""
|
|
Define name for referencing matching tokens as a nested attribute
|
|
of the returned parse results.
|
|
NOTE: this returns a *copy* of the original C{ParserElement} object;
|
|
this is so that the client can define a basic element, such as an
|
|
integer, and reference it in multiple places with different names.
|
|
|
|
You can also set results names using the abbreviated syntax,
|
|
C{expr("name")} in place of C{expr.setResultsName("name")} -
|
|
see L{I{__call__}<__call__>}.
|
|
|
|
Example::
|
|
date_str = (integer.setResultsName("year") + '/'
|
|
+ integer.setResultsName("month") + '/'
|
|
+ integer.setResultsName("day"))
|
|
|
|
# equivalent form:
|
|
date_str = integer("year") + '/' + integer("month") + '/' + integer("day")
|
|
"""
|
|
newself = self.copy()
|
|
if name.endswith("*"):
|
|
name = name[:-1]
|
|
listAllMatches=True
|
|
newself.resultsName = name
|
|
newself.modalResults = not listAllMatches
|
|
return newself
|
|
|
|
def setBreak(self,breakFlag = True):
|
|
"""Method to invoke the Python pdb debugger when this element is
|
|
about to be parsed. Set C{breakFlag} to True to enable, False to
|
|
disable.
|
|
"""
|
|
if breakFlag:
|
|
_parseMethod = self._parse
|
|
def breaker(instring, loc, doActions=True, callPreParse=True):
|
|
import pdb
|
|
pdb.set_trace()
|
|
return _parseMethod( instring, loc, doActions, callPreParse )
|
|
breaker._originalParseMethod = _parseMethod
|
|
self._parse = breaker
|
|
else:
|
|
if hasattr(self._parse,"_originalParseMethod"):
|
|
self._parse = self._parse._originalParseMethod
|
|
return self
|
|
|
|
def setParseAction( self, *fns, **kwargs ):
|
|
"""
|
|
Define one or more actions to perform when successfully matching parse element definition.
|
|
Parse action fn is a callable method with 0-3 arguments, called as C{fn(s,loc,toks)},
|
|
C{fn(loc,toks)}, C{fn(toks)}, or just C{fn()}, where:
|
|
- s = the original string being parsed (see note below)
|
|
- loc = the location of the matching substring
|
|
- toks = a list of the matched tokens, packaged as a C{L{ParseResults}} object
|
|
If the functions in fns modify the tokens, they can return them as the return
|
|
value from fn, and the modified list of tokens will replace the original.
|
|
Otherwise, fn does not need to return any value.
|
|
|
|
Optional keyword arguments:
|
|
- callDuringTry = (default=C{False}) indicate if parse action should be run during lookaheads and alternate testing
|
|
|
|
Note: the default parsing behavior is to expand tabs in the input string
|
|
before starting the parsing process. See L{I{parseString}<parseString>} for more information
|
|
on parsing strings containing C{<TAB>}s, and suggested methods to maintain a
|
|
consistent view of the parsed string, the parse location, and line and column
|
|
positions within the parsed string.
|
|
|
|
Example::
|
|
integer = Word(nums)
|
|
date_str = integer + '/' + integer + '/' + integer
|
|
|
|
date_str.parseString("1999/12/31") # -> ['1999', '/', '12', '/', '31']
|
|
|
|
# use parse action to convert to ints at parse time
|
|
integer = Word(nums).setParseAction(lambda toks: int(toks[0]))
|
|
date_str = integer + '/' + integer + '/' + integer
|
|
|
|
# note that integer fields are now ints, not strings
|
|
date_str.parseString("1999/12/31") # -> [1999, '/', 12, '/', 31]
|
|
"""
|
|
self.parseAction = list(map(_trim_arity, list(fns)))
|
|
self.callDuringTry = kwargs.get("callDuringTry", False)
|
|
return self
|
|
|
|
def addParseAction( self, *fns, **kwargs ):
|
|
"""
|
|
Add one or more parse actions to expression's list of parse actions. See L{I{setParseAction}<setParseAction>}.
|
|
|
|
See examples in L{I{copy}<copy>}.
|
|
"""
|
|
self.parseAction += list(map(_trim_arity, list(fns)))
|
|
self.callDuringTry = self.callDuringTry or kwargs.get("callDuringTry", False)
|
|
return self
|
|
|
|
def addCondition(self, *fns, **kwargs):
|
|
"""Add a boolean predicate function to expression's list of parse actions. See
|
|
L{I{setParseAction}<setParseAction>} for function call signatures. Unlike C{setParseAction},
|
|
functions passed to C{addCondition} need to return boolean success/fail of the condition.
|
|
|
|
Optional keyword arguments:
|
|
- message = define a custom message to be used in the raised exception
|
|
- fatal = if True, will raise ParseFatalException to stop parsing immediately; otherwise will raise ParseException
|
|
|
|
Example::
|
|
integer = Word(nums).setParseAction(lambda toks: int(toks[0]))
|
|
year_int = integer.copy()
|
|
year_int.addCondition(lambda toks: toks[0] >= 2000, message="Only support years 2000 and later")
|
|
date_str = year_int + '/' + integer + '/' + integer
|
|
|
|
result = date_str.parseString("1999/12/31") # -> Exception: Only support years 2000 and later (at char 0), (line:1, col:1)
|
|
"""
|
|
msg = kwargs.get("message", "failed user-defined condition")
|
|
exc_type = ParseFatalException if kwargs.get("fatal", False) else ParseException
|
|
for fn in fns:
|
|
def pa(s,l,t):
|
|
if not bool(_trim_arity(fn)(s,l,t)):
|
|
raise exc_type(s,l,msg)
|
|
self.parseAction.append(pa)
|
|
self.callDuringTry = self.callDuringTry or kwargs.get("callDuringTry", False)
|
|
return self
|
|
|
|
def setFailAction( self, fn ):
|
|
"""Define action to perform if parsing fails at this expression.
|
|
Fail acton fn is a callable function that takes the arguments
|
|
C{fn(s,loc,expr,err)} where:
|
|
- s = string being parsed
|
|
- loc = location where expression match was attempted and failed
|
|
- expr = the parse expression that failed
|
|
- err = the exception thrown
|
|
The function returns no value. It may throw C{L{ParseFatalException}}
|
|
if it is desired to stop parsing immediately."""
|
|
self.failAction = fn
|
|
return self
|
|
|
|
def _skipIgnorables( self, instring, loc ):
|
|
exprsFound = True
|
|
while exprsFound:
|
|
exprsFound = False
|
|
for e in self.ignoreExprs:
|
|
try:
|
|
while 1:
|
|
loc,dummy = e._parse( instring, loc )
|
|
exprsFound = True
|
|
except ParseException:
|
|
pass
|
|
return loc
|
|
|
|
def preParse( self, instring, loc ):
|
|
if self.ignoreExprs:
|
|
loc = self._skipIgnorables( instring, loc )
|
|
|
|
if self.skipWhitespace:
|
|
wt = self.whiteChars
|
|
instrlen = len(instring)
|
|
while loc < instrlen and instring[loc] in wt:
|
|
loc += 1
|
|
|
|
return loc
|
|
|
|
def parseImpl( self, instring, loc, doActions=True ):
|
|
return loc, []
|
|
|
|
def postParse( self, instring, loc, tokenlist ):
|
|
return tokenlist
|
|
|
|
#~ @profile
|
|
def _parseNoCache( self, instring, loc, doActions=True, callPreParse=True ):
|
|
debugging = ( self.debug ) #and doActions )
|
|
|
|
if debugging or self.failAction:
|
|
#~ print ("Match",self,"at loc",loc,"(%d,%d)" % ( lineno(loc,instring), col(loc,instring) ))
|
|
if (self.debugActions[0] ):
|
|
self.debugActions[0]( instring, loc, self )
|
|
if callPreParse and self.callPreparse:
|
|
preloc = self.preParse( instring, loc )
|
|
else:
|
|
preloc = loc
|
|
tokensStart = preloc
|
|
try:
|
|
try:
|
|
loc,tokens = self.parseImpl( instring, preloc, doActions )
|
|
except IndexError:
|
|
raise ParseException( instring, len(instring), self.errmsg, self )
|
|
except ParseBaseException as err:
|
|
#~ print ("Exception raised:", err)
|
|
if self.debugActions[2]:
|
|
self.debugActions[2]( instring, tokensStart, self, err )
|
|
if self.failAction:
|
|
self.failAction( instring, tokensStart, self, err )
|
|
raise
|
|
else:
|
|
if callPreParse and self.callPreparse:
|
|
preloc = self.preParse( instring, loc )
|
|
else:
|
|
preloc = loc
|
|
tokensStart = preloc
|
|
if self.mayIndexError or preloc >= len(instring):
|
|
try:
|
|
loc,tokens = self.parseImpl( instring, preloc, doActions )
|
|
except IndexError:
|
|
raise ParseException( instring, len(instring), self.errmsg, self )
|
|
else:
|
|
loc,tokens = self.parseImpl( instring, preloc, doActions )
|
|
|
|
tokens = self.postParse( instring, loc, tokens )
|
|
|
|
retTokens = ParseResults( tokens, self.resultsName, asList=self.saveAsList, modal=self.modalResults )
|
|
if self.parseAction and (doActions or self.callDuringTry):
|
|
if debugging:
|
|
try:
|
|
for fn in self.parseAction:
|
|
tokens = fn( instring, tokensStart, retTokens )
|
|
if tokens is not None:
|
|
retTokens = ParseResults( tokens,
|
|
self.resultsName,
|
|
asList=self.saveAsList and isinstance(tokens,(ParseResults,list)),
|
|
modal=self.modalResults )
|
|
except ParseBaseException as err:
|
|
#~ print "Exception raised in user parse action:", err
|
|
if (self.debugActions[2] ):
|
|
self.debugActions[2]( instring, tokensStart, self, err )
|
|
raise
|
|
else:
|
|
for fn in self.parseAction:
|
|
tokens = fn( instring, tokensStart, retTokens )
|
|
if tokens is not None:
|
|
retTokens = ParseResults( tokens,
|
|
self.resultsName,
|
|
asList=self.saveAsList and isinstance(tokens,(ParseResults,list)),
|
|
modal=self.modalResults )
|
|
if debugging:
|
|
#~ print ("Matched",self,"->",retTokens.asList())
|
|
if (self.debugActions[1] ):
|
|
self.debugActions[1]( instring, tokensStart, loc, self, retTokens )
|
|
|
|
return loc, retTokens
|
|
|
|
def tryParse( self, instring, loc ):
|
|
try:
|
|
return self._parse( instring, loc, doActions=False )[0]
|
|
except ParseFatalException:
|
|
raise ParseException( instring, loc, self.errmsg, self)
|
|
|
|
def canParseNext(self, instring, loc):
|
|
try:
|
|
self.tryParse(instring, loc)
|
|
except (ParseException, IndexError):
|
|
return False
|
|
else:
|
|
return True
|
|
|
|
class _UnboundedCache(object):
|
|
def __init__(self):
|
|
cache = {}
|
|
self.not_in_cache = not_in_cache = object()
|
|
|
|
def get(self, key):
|
|
return cache.get(key, not_in_cache)
|
|
|
|
def set(self, key, value):
|
|
cache[key] = value
|
|
|
|
def clear(self):
|
|
cache.clear()
|
|
|
|
def cache_len(self):
|
|
return len(cache)
|
|
|
|
self.get = types.MethodType(get, self)
|
|
self.set = types.MethodType(set, self)
|
|
self.clear = types.MethodType(clear, self)
|
|
self.__len__ = types.MethodType(cache_len, self)
|
|
|
|
if _OrderedDict is not None:
|
|
class _FifoCache(object):
|
|
def __init__(self, size):
|
|
self.not_in_cache = not_in_cache = object()
|
|
|
|
cache = _OrderedDict()
|
|
|
|
def get(self, key):
|
|
return cache.get(key, not_in_cache)
|
|
|
|
def set(self, key, value):
|
|
cache[key] = value
|
|
while len(cache) > size:
|
|
try:
|
|
cache.popitem(False)
|
|
except KeyError:
|
|
pass
|
|
|
|
def clear(self):
|
|
cache.clear()
|
|
|
|
def cache_len(self):
|
|
return len(cache)
|
|
|
|
self.get = types.MethodType(get, self)
|
|
self.set = types.MethodType(set, self)
|
|
self.clear = types.MethodType(clear, self)
|
|
self.__len__ = types.MethodType(cache_len, self)
|
|
|
|
else:
|
|
class _FifoCache(object):
|
|
def __init__(self, size):
|
|
self.not_in_cache = not_in_cache = object()
|
|
|
|
cache = {}
|
|
key_fifo = collections.deque([], size)
|
|
|
|
def get(self, key):
|
|
return cache.get(key, not_in_cache)
|
|
|
|
def set(self, key, value):
|
|
cache[key] = value
|
|
while len(key_fifo) > size:
|
|
cache.pop(key_fifo.popleft(), None)
|
|
key_fifo.append(key)
|
|
|
|
def clear(self):
|
|
cache.clear()
|
|
key_fifo.clear()
|
|
|
|
def cache_len(self):
|
|
return len(cache)
|
|
|
|
self.get = types.MethodType(get, self)
|
|
self.set = types.MethodType(set, self)
|
|
self.clear = types.MethodType(clear, self)
|
|
self.__len__ = types.MethodType(cache_len, self)
|
|
|
|
# argument cache for optimizing repeated calls when backtracking through recursive expressions
|
|
packrat_cache = {} # this is set later by enabledPackrat(); this is here so that resetCache() doesn't fail
|
|
packrat_cache_lock = RLock()
|
|
packrat_cache_stats = [0, 0]
|
|
|
|
# this method gets repeatedly called during backtracking with the same arguments -
|
|
# we can cache these arguments and save ourselves the trouble of re-parsing the contained expression
|
|
def _parseCache( self, instring, loc, doActions=True, callPreParse=True ):
|
|
HIT, MISS = 0, 1
|
|
lookup = (self, instring, loc, callPreParse, doActions)
|
|
with ParserElement.packrat_cache_lock:
|
|
cache = ParserElement.packrat_cache
|
|
value = cache.get(lookup)
|
|
if value is cache.not_in_cache:
|
|
ParserElement.packrat_cache_stats[MISS] += 1
|
|
try:
|
|
value = self._parseNoCache(instring, loc, doActions, callPreParse)
|
|
except ParseBaseException as pe:
|
|
# cache a copy of the exception, without the traceback
|
|
cache.set(lookup, pe.__class__(*pe.args))
|
|
raise
|
|
else:
|
|
cache.set(lookup, (value[0], value[1].copy()))
|
|
return value
|
|
else:
|
|
ParserElement.packrat_cache_stats[HIT] += 1
|
|
if isinstance(value, Exception):
|
|
raise value
|
|
return (value[0], value[1].copy())
|
|
|
|
_parse = _parseNoCache
|
|
|
|
@staticmethod
|
|
def resetCache():
|
|
ParserElement.packrat_cache.clear()
|
|
ParserElement.packrat_cache_stats[:] = [0] * len(ParserElement.packrat_cache_stats)
|
|
|
|
_packratEnabled = False
|
|
@staticmethod
|
|
def enablePackrat(cache_size_limit=128):
|
|
"""Enables "packrat" parsing, which adds memoizing to the parsing logic.
|
|
Repeated parse attempts at the same string location (which happens
|
|
often in many complex grammars) can immediately return a cached value,
|
|
instead of re-executing parsing/validating code. Memoizing is done of
|
|
both valid results and parsing exceptions.
|
|
|
|
Parameters:
|
|
- cache_size_limit - (default=C{128}) - if an integer value is provided
|
|
will limit the size of the packrat cache; if None is passed, then
|
|
the cache size will be unbounded; if 0 is passed, the cache will
|
|
be effectively disabled.
|
|
|
|
This speedup may break existing programs that use parse actions that
|
|
have side-effects. For this reason, packrat parsing is disabled when
|
|
you first import pyparsing. To activate the packrat feature, your
|
|
program must call the class method C{ParserElement.enablePackrat()}. If
|
|
your program uses C{psyco} to "compile as you go", you must call
|
|
C{enablePackrat} before calling C{psyco.full()}. If you do not do this,
|
|
Python will crash. For best results, call C{enablePackrat()} immediately
|
|
after importing pyparsing.
|
|
|
|
Example::
|
|
import pyparsing
|
|
pyparsing.ParserElement.enablePackrat()
|
|
"""
|
|
if not ParserElement._packratEnabled:
|
|
ParserElement._packratEnabled = True
|
|
if cache_size_limit is None:
|
|
ParserElement.packrat_cache = ParserElement._UnboundedCache()
|
|
else:
|
|
ParserElement.packrat_cache = ParserElement._FifoCache(cache_size_limit)
|
|
ParserElement._parse = ParserElement._parseCache
|
|
|
|
def parseString( self, instring, parseAll=False ):
|
|
"""
|
|
Execute the parse expression with the given string.
|
|
This is the main interface to the client code, once the complete
|
|
expression has been built.
|
|
|
|
If you want the grammar to require that the entire input string be
|
|
successfully parsed, then set C{parseAll} to True (equivalent to ending
|
|
the grammar with C{L{StringEnd()}}).
|
|
|
|
Note: C{parseString} implicitly calls C{expandtabs()} on the input string,
|
|
in order to report proper column numbers in parse actions.
|
|
If the input string contains tabs and
|
|
the grammar uses parse actions that use the C{loc} argument to index into the
|
|
string being parsed, you can ensure you have a consistent view of the input
|
|
string by:
|
|
- calling C{parseWithTabs} on your grammar before calling C{parseString}
|
|
(see L{I{parseWithTabs}<parseWithTabs>})
|
|
- define your parse action using the full C{(s,loc,toks)} signature, and
|
|
reference the input string using the parse action's C{s} argument
|
|
- explictly expand the tabs in your input string before calling
|
|
C{parseString}
|
|
|
|
Example::
|
|
Word('a').parseString('aaaaabaaa') # -> ['aaaaa']
|
|
Word('a').parseString('aaaaabaaa', parseAll=True) # -> Exception: Expected end of text
|
|
"""
|
|
ParserElement.resetCache()
|
|
if not self.streamlined:
|
|
self.streamline()
|
|
#~ self.saveAsList = True
|
|
for e in self.ignoreExprs:
|
|
e.streamline()
|
|
if not self.keepTabs:
|
|
instring = instring.expandtabs()
|
|
try:
|
|
loc, tokens = self._parse( instring, 0 )
|
|
if parseAll:
|
|
loc = self.preParse( instring, loc )
|
|
se = Empty() + StringEnd()
|
|
se._parse( instring, loc )
|
|
except ParseBaseException as exc:
|
|
if ParserElement.verbose_stacktrace:
|
|
raise
|
|
else:
|
|
# catch and re-raise exception from here, clears out pyparsing internal stack trace
|
|
raise exc
|
|
else:
|
|
return tokens
|
|
|
|
def scanString( self, instring, maxMatches=_MAX_INT, overlap=False ):
|
|
"""
|
|
Scan the input string for expression matches. Each match will return the
|
|
matching tokens, start location, and end location. May be called with optional
|
|
C{maxMatches} argument, to clip scanning after 'n' matches are found. If
|
|
C{overlap} is specified, then overlapping matches will be reported.
|
|
|
|
Note that the start and end locations are reported relative to the string
|
|
being parsed. See L{I{parseString}<parseString>} for more information on parsing
|
|
strings with embedded tabs.
|
|
|
|
Example::
|
|
source = "sldjf123lsdjjkf345sldkjf879lkjsfd987"
|
|
print(source)
|
|
for tokens,start,end in Word(alphas).scanString(source):
|
|
print(' '*start + '^'*(end-start))
|
|
print(' '*start + tokens[0])
|
|
|
|
prints::
|
|
|
|
sldjf123lsdjjkf345sldkjf879lkjsfd987
|
|
^^^^^
|
|
sldjf
|
|
^^^^^^^
|
|
lsdjjkf
|
|
^^^^^^
|
|
sldkjf
|
|
^^^^^^
|
|
lkjsfd
|
|
"""
|
|
if not self.streamlined:
|
|
self.streamline()
|
|
for e in self.ignoreExprs:
|
|
e.streamline()
|
|
|
|
if not self.keepTabs:
|
|
instring = _ustr(instring).expandtabs()
|
|
instrlen = len(instring)
|
|
loc = 0
|
|
preparseFn = self.preParse
|
|
parseFn = self._parse
|
|
ParserElement.resetCache()
|
|
matches = 0
|
|
try:
|
|
while loc <= instrlen and matches < maxMatches:
|
|
try:
|
|
preloc = preparseFn( instring, loc )
|
|
nextLoc,tokens = parseFn( instring, preloc, callPreParse=False )
|
|
except ParseException:
|
|
loc = preloc+1
|
|
else:
|
|
if nextLoc > loc:
|
|
matches += 1
|
|
yield tokens, preloc, nextLoc
|
|
if overlap:
|
|
nextloc = preparseFn( instring, loc )
|
|
if nextloc > loc:
|
|
loc = nextLoc
|
|
else:
|
|
loc += 1
|
|
else:
|
|
loc = nextLoc
|
|
else:
|
|
loc = preloc+1
|
|
except ParseBaseException as exc:
|
|
if ParserElement.verbose_stacktrace:
|
|
raise
|
|
else:
|
|
# catch and re-raise exception from here, clears out pyparsing internal stack trace
|
|
raise exc
|
|
|
|
def transformString( self, instring ):
|
|
"""
|
|
Extension to C{L{scanString}}, to modify matching text with modified tokens that may
|
|
be returned from a parse action. To use C{transformString}, define a grammar and
|
|
attach a parse action to it that modifies the returned token list.
|
|
Invoking C{transformString()} on a target string will then scan for matches,
|
|
and replace the matched text patterns according to the logic in the parse
|
|
action. C{transformString()} returns the resulting transformed string.
|
|
|
|
Example::
|
|
wd = Word(alphas)
|
|
wd.setParseAction(lambda toks: toks[0].title())
|
|
|
|
print(wd.transformString("now is the winter of our discontent made glorious summer by this sun of york."))
|
|
Prints::
|
|
Now Is The Winter Of Our Discontent Made Glorious Summer By This Sun Of York.
|
|
"""
|
|
out = []
|
|
lastE = 0
|
|
# force preservation of <TAB>s, to minimize unwanted transformation of string, and to
|
|
# keep string locs straight between transformString and scanString
|
|
self.keepTabs = True
|
|
try:
|
|
for t,s,e in self.scanString( instring ):
|
|
out.append( instring[lastE:s] )
|
|
if t:
|
|
if isinstance(t,ParseResults):
|
|
out += t.asList()
|
|
elif isinstance(t,list):
|
|
out += t
|
|
else:
|
|
out.append(t)
|
|
lastE = e
|
|
out.append(instring[lastE:])
|
|
out = [o for o in out if o]
|
|
return "".join(map(_ustr,_flatten(out)))
|
|
except ParseBaseException as exc:
|
|
if ParserElement.verbose_stacktrace:
|
|
raise
|
|
else:
|
|
# catch and re-raise exception from here, clears out pyparsing internal stack trace
|
|
raise exc
|
|
|
|
def searchString( self, instring, maxMatches=_MAX_INT ):
|
|
"""
|
|
Another extension to C{L{scanString}}, simplifying the access to the tokens found
|
|
to match the given parse expression. May be called with optional
|
|
C{maxMatches} argument, to clip searching after 'n' matches are found.
|
|
|
|
Example::
|
|
# a capitalized word starts with an uppercase letter, followed by zero or more lowercase letters
|
|
cap_word = Word(alphas.upper(), alphas.lower())
|
|
|
|
print(cap_word.searchString("More than Iron, more than Lead, more than Gold I need Electricity"))
|
|
|
|
# the sum() builtin can be used to merge results into a single ParseResults object
|
|
print(sum(cap_word.searchString("More than Iron, more than Lead, more than Gold I need Electricity")))
|
|
prints::
|
|
[['More'], ['Iron'], ['Lead'], ['Gold'], ['I'], ['Electricity']]
|
|
['More', 'Iron', 'Lead', 'Gold', 'I', 'Electricity']
|
|
"""
|
|
try:
|
|
return ParseResults([ t for t,s,e in self.scanString( instring, maxMatches ) ])
|
|
except ParseBaseException as exc:
|
|
if ParserElement.verbose_stacktrace:
|
|
raise
|
|
else:
|
|
# catch and re-raise exception from here, clears out pyparsing internal stack trace
|
|
raise exc
|
|
|
|
def split(self, instring, maxsplit=_MAX_INT, includeSeparators=False):
|
|
"""
|
|
Generator method to split a string using the given expression as a separator.
|
|
May be called with optional C{maxsplit} argument, to limit the number of splits;
|
|
and the optional C{includeSeparators} argument (default=C{False}), if the separating
|
|
matching text should be included in the split results.
|
|
|
|
Example::
|
|
punc = oneOf(list(".,;:/-!?"))
|
|
print(list(punc.split("This, this?, this sentence, is badly punctuated!")))
|
|
prints::
|
|
['This', ' this', '', ' this sentence', ' is badly punctuated', '']
|
|
"""
|
|
splits = 0
|
|
last = 0
|
|
for t,s,e in self.scanString(instring, maxMatches=maxsplit):
|
|
yield instring[last:s]
|
|
if includeSeparators:
|
|
yield t[0]
|
|
last = e
|
|
yield instring[last:]
|
|
|
|
def __add__(self, other ):
|
|
"""
|
|
Implementation of + operator - returns C{L{And}}. Adding strings to a ParserElement
|
|
converts them to L{Literal}s by default.
|
|
|
|
Example::
|
|
greet = Word(alphas) + "," + Word(alphas) + "!"
|
|
hello = "Hello, World!"
|
|
print (hello, "->", greet.parseString(hello))
|
|
Prints::
|
|
Hello, World! -> ['Hello', ',', 'World', '!']
|
|
"""
|
|
if isinstance( other, basestring ):
|
|
other = ParserElement._literalStringClass( other )
|
|
if not isinstance( other, ParserElement ):
|
|
warnings.warn("Cannot combine element of type %s with ParserElement" % type(other),
|
|
SyntaxWarning, stacklevel=2)
|
|
return None
|
|
return And( [ self, other ] )
|
|
|
|
def __radd__(self, other ):
|
|
"""
|
|
Implementation of + operator when left operand is not a C{L{ParserElement}}
|
|
"""
|
|
if isinstance( other, basestring ):
|
|
other = ParserElement._literalStringClass( other )
|
|
if not isinstance( other, ParserElement ):
|
|
warnings.warn("Cannot combine element of type %s with ParserElement" % type(other),
|
|
SyntaxWarning, stacklevel=2)
|
|
return None
|
|
return other + self
|
|
|
|
def __sub__(self, other):
|
|
"""
|
|
Implementation of - operator, returns C{L{And}} with error stop
|
|
"""
|
|
if isinstance( other, basestring ):
|
|
other = ParserElement._literalStringClass( other )
|
|
if not isinstance( other, ParserElement ):
|
|
warnings.warn("Cannot combine element of type %s with ParserElement" % type(other),
|
|
SyntaxWarning, stacklevel=2)
|
|
return None
|
|
return self + And._ErrorStop() + other
|
|
|
|
def __rsub__(self, other ):
|
|
"""
|
|
Implementation of - operator when left operand is not a C{L{ParserElement}}
|
|
"""
|
|
if isinstance( other, basestring ):
|
|
other = ParserElement._literalStringClass( other )
|
|
if not isinstance( other, ParserElement ):
|
|
warnings.warn("Cannot combine element of type %s with ParserElement" % type(other),
|
|
SyntaxWarning, stacklevel=2)
|
|
return None
|
|
return other - self
|
|
|
|
def __mul__(self,other):
|
|
"""
|
|
Implementation of * operator, allows use of C{expr * 3} in place of
|
|
C{expr + expr + expr}. Expressions may also me multiplied by a 2-integer
|
|
tuple, similar to C{{min,max}} multipliers in regular expressions. Tuples
|
|
may also include C{None} as in:
|
|
- C{expr*(n,None)} or C{expr*(n,)} is equivalent
|
|
to C{expr*n + L{ZeroOrMore}(expr)}
|
|
(read as "at least n instances of C{expr}")
|
|
- C{expr*(None,n)} is equivalent to C{expr*(0,n)}
|
|
(read as "0 to n instances of C{expr}")
|
|
- C{expr*(None,None)} is equivalent to C{L{ZeroOrMore}(expr)}
|
|
- C{expr*(1,None)} is equivalent to C{L{OneOrMore}(expr)}
|
|
|
|
Note that C{expr*(None,n)} does not raise an exception if
|
|
more than n exprs exist in the input stream; that is,
|
|
C{expr*(None,n)} does not enforce a maximum number of expr
|
|
occurrences. If this behavior is desired, then write
|
|
C{expr*(None,n) + ~expr}
|
|
"""
|
|
if isinstance(other,int):
|
|
minElements, optElements = other,0
|
|
elif isinstance(other,tuple):
|
|
other = (other + (None, None))[:2]
|
|
if other[0] is None:
|
|
other = (0, other[1])
|
|
if isinstance(other[0],int) and other[1] is None:
|
|
if other[0] == 0:
|
|
return ZeroOrMore(self)
|
|
if other[0] == 1:
|
|
return OneOrMore(self)
|
|
else:
|
|
return self*other[0] + ZeroOrMore(self)
|
|
elif isinstance(other[0],int) and isinstance(other[1],int):
|
|
minElements, optElements = other
|
|
optElements -= minElements
|
|
else:
|
|
raise TypeError("cannot multiply 'ParserElement' and ('%s','%s') objects", type(other[0]),type(other[1]))
|
|
else:
|
|
raise TypeError("cannot multiply 'ParserElement' and '%s' objects", type(other))
|
|
|
|
if minElements < 0:
|
|
raise ValueError("cannot multiply ParserElement by negative value")
|
|
if optElements < 0:
|
|
raise ValueError("second tuple value must be greater or equal to first tuple value")
|
|
if minElements == optElements == 0:
|
|
raise ValueError("cannot multiply ParserElement by 0 or (0,0)")
|
|
|
|
if (optElements):
|
|
def makeOptionalList(n):
|
|
if n>1:
|
|
return Optional(self + makeOptionalList(n-1))
|
|
else:
|
|
return Optional(self)
|
|
if minElements:
|
|
if minElements == 1:
|
|
ret = self + makeOptionalList(optElements)
|
|
else:
|
|
ret = And([self]*minElements) + makeOptionalList(optElements)
|
|
else:
|
|
ret = makeOptionalList(optElements)
|
|
else:
|
|
if minElements == 1:
|
|
ret = self
|
|
else:
|
|
ret = And([self]*minElements)
|
|
return ret
|
|
|
|
def __rmul__(self, other):
|
|
return self.__mul__(other)
|
|
|
|
def __or__(self, other ):
|
|
"""
|
|
Implementation of | operator - returns C{L{MatchFirst}}
|
|
"""
|
|
if isinstance( other, basestring ):
|
|
other = ParserElement._literalStringClass( other )
|
|
if not isinstance( other, ParserElement ):
|
|
warnings.warn("Cannot combine element of type %s with ParserElement" % type(other),
|
|
SyntaxWarning, stacklevel=2)
|
|
return None
|
|
return MatchFirst( [ self, other ] )
|
|
|
|
def __ror__(self, other ):
|
|
"""
|
|
Implementation of | operator when left operand is not a C{L{ParserElement}}
|
|
"""
|
|
if isinstance( other, basestring ):
|
|
other = ParserElement._literalStringClass( other )
|
|
if not isinstance( other, ParserElement ):
|
|
warnings.warn("Cannot combine element of type %s with ParserElement" % type(other),
|
|
SyntaxWarning, stacklevel=2)
|
|
return None
|
|
return other | self
|
|
|
|
def __xor__(self, other ):
|
|
"""
|
|
Implementation of ^ operator - returns C{L{Or}}
|
|
"""
|
|
if isinstance( other, basestring ):
|
|
other = ParserElement._literalStringClass( other )
|
|
if not isinstance( other, ParserElement ):
|
|
warnings.warn("Cannot combine element of type %s with ParserElement" % type(other),
|
|
SyntaxWarning, stacklevel=2)
|
|
return None
|
|
return Or( [ self, other ] )
|
|
|
|
def __rxor__(self, other ):
|
|
"""
|
|
Implementation of ^ operator when left operand is not a C{L{ParserElement}}
|
|
"""
|
|
if isinstance( other, basestring ):
|
|
other = ParserElement._literalStringClass( other )
|
|
if not isinstance( other, ParserElement ):
|
|
warnings.warn("Cannot combine element of type %s with ParserElement" % type(other),
|
|
SyntaxWarning, stacklevel=2)
|
|
return None
|
|
return other ^ self
|
|
|
|
def __and__(self, other ):
|
|
"""
|
|
Implementation of & operator - returns C{L{Each}}
|
|
"""
|
|
if isinstance( other, basestring ):
|
|
other = ParserElement._literalStringClass( other )
|
|
if not isinstance( other, ParserElement ):
|
|
warnings.warn("Cannot combine element of type %s with ParserElement" % type(other),
|
|
SyntaxWarning, stacklevel=2)
|
|
return None
|
|
return Each( [ self, other ] )
|
|
|
|
def __rand__(self, other ):
|
|
"""
|
|
Implementation of & operator when left operand is not a C{L{ParserElement}}
|
|
"""
|
|
if isinstance( other, basestring ):
|
|
other = ParserElement._literalStringClass( other )
|
|
if not isinstance( other, ParserElement ):
|
|
warnings.warn("Cannot combine element of type %s with ParserElement" % type(other),
|
|
SyntaxWarning, stacklevel=2)
|
|
return None
|
|
return other & self
|
|
|
|
def __invert__( self ):
|
|
"""
|
|
Implementation of ~ operator - returns C{L{NotAny}}
|
|
"""
|
|
return NotAny( self )
|
|
|
|
def __call__(self, name=None):
|
|
"""
|
|
Shortcut for C{L{setResultsName}}, with C{listAllMatches=False}.
|
|
|
|
If C{name} is given with a trailing C{'*'} character, then C{listAllMatches} will be
|
|
passed as C{True}.
|
|
|
|
If C{name} is omitted, same as calling C{L{copy}}.
|
|
|
|
Example::
|
|
# these are equivalent
|
|
userdata = Word(alphas).setResultsName("name") + Word(nums+"-").setResultsName("socsecno")
|
|
userdata = Word(alphas)("name") + Word(nums+"-")("socsecno")
|
|
"""
|
|
if name is not None:
|
|
return self.setResultsName(name)
|
|
else:
|
|
return self.copy()
|
|
|
|
def suppress( self ):
|
|
"""
|
|
Suppresses the output of this C{ParserElement}; useful to keep punctuation from
|
|
cluttering up returned output.
|
|
"""
|
|
return Suppress( self )
|
|
|
|
def leaveWhitespace( self ):
|
|
"""
|
|
Disables the skipping of whitespace before matching the characters in the
|
|
C{ParserElement}'s defined pattern. This is normally only used internally by
|
|
the pyparsing module, but may be needed in some whitespace-sensitive grammars.
|
|
"""
|
|
self.skipWhitespace = False
|
|
return self
|
|
|
|
def setWhitespaceChars( self, chars ):
|
|
"""
|
|
Overrides the default whitespace chars
|
|
"""
|
|
self.skipWhitespace = True
|
|
self.whiteChars = chars
|
|
self.copyDefaultWhiteChars = False
|
|
return self
|
|
|
|
def parseWithTabs( self ):
|
|
"""
|
|
Overrides default behavior to expand C{<TAB>}s to spaces before parsing the input string.
|
|
Must be called before C{parseString} when the input grammar contains elements that
|
|
match C{<TAB>} characters.
|
|
"""
|
|
self.keepTabs = True
|
|
return self
|
|
|
|
def ignore( self, other ):
|
|
"""
|
|
Define expression to be ignored (e.g., comments) while doing pattern
|
|
matching; may be called repeatedly, to define multiple comment or other
|
|
ignorable patterns.
|
|
|
|
Example::
|
|
patt = OneOrMore(Word(alphas))
|
|
patt.parseString('ablaj /* comment */ lskjd') # -> ['ablaj']
|
|
|
|
patt.ignore(cStyleComment)
|
|
patt.parseString('ablaj /* comment */ lskjd') # -> ['ablaj', 'lskjd']
|
|
"""
|
|
if isinstance(other, basestring):
|
|
other = Suppress(other)
|
|
|
|
if isinstance( other, Suppress ):
|
|
if other not in self.ignoreExprs:
|
|
self.ignoreExprs.append(other)
|
|
else:
|
|
self.ignoreExprs.append( Suppress( other.copy() ) )
|
|
return self
|
|
|
|
def setDebugActions( self, startAction, successAction, exceptionAction ):
|
|
"""
|
|
Enable display of debugging messages while doing pattern matching.
|
|
"""
|
|
self.debugActions = (startAction or _defaultStartDebugAction,
|
|
successAction or _defaultSuccessDebugAction,
|
|
exceptionAction or _defaultExceptionDebugAction)
|
|
self.debug = True
|
|
return self
|
|
|
|
def setDebug( self, flag=True ):
|
|
"""
|
|
Enable display of debugging messages while doing pattern matching.
|
|
Set C{flag} to True to enable, False to disable.
|
|
|
|
Example::
|
|
wd = Word(alphas).setName("alphaword")
|
|
integer = Word(nums).setName("numword")
|
|
term = wd | integer
|
|
|
|
# turn on debugging for wd
|
|
wd.setDebug()
|
|
|
|
OneOrMore(term).parseString("abc 123 xyz 890")
|
|
|
|
prints::
|
|
Match alphaword at loc 0(1,1)
|
|
Matched alphaword -> ['abc']
|
|
Match alphaword at loc 3(1,4)
|
|
Exception raised:Expected alphaword (at char 4), (line:1, col:5)
|
|
Match alphaword at loc 7(1,8)
|
|
Matched alphaword -> ['xyz']
|
|
Match alphaword at loc 11(1,12)
|
|
Exception raised:Expected alphaword (at char 12), (line:1, col:13)
|
|
Match alphaword at loc 15(1,16)
|
|
Exception raised:Expected alphaword (at char 15), (line:1, col:16)
|
|
|
|
The output shown is that produced by the default debug actions - custom debug actions can be
|
|
specified using L{setDebugActions}. Prior to attempting
|
|
to match the C{wd} expression, the debugging message C{"Match <exprname> at loc <n>(<line>,<col>)"}
|
|
is shown. Then if the parse succeeds, a C{"Matched"} message is shown, or an C{"Exception raised"}
|
|
message is shown. Also note the use of L{setName} to assign a human-readable name to the expression,
|
|
which makes debugging and exception messages easier to understand - for instance, the default
|
|
name created for the C{Word} expression without calling C{setName} is C{"W:(ABCD...)"}.
|
|
"""
|
|
if flag:
|
|
self.setDebugActions( _defaultStartDebugAction, _defaultSuccessDebugAction, _defaultExceptionDebugAction )
|
|
else:
|
|
self.debug = False
|
|
return self
|
|
|
|
def __str__( self ):
|
|
return self.name
|
|
|
|
def __repr__( self ):
|
|
return _ustr(self)
|
|
|
|
def streamline( self ):
|
|
self.streamlined = True
|
|
self.strRepr = None
|
|
return self
|
|
|
|
def checkRecursion( self, parseElementList ):
|
|
pass
|
|
|
|
def validate( self, validateTrace=[] ):
|
|
"""
|
|
Check defined expressions for valid structure, check for infinite recursive definitions.
|
|
"""
|
|
self.checkRecursion( [] )
|
|
|
|
def parseFile( self, file_or_filename, parseAll=False ):
|
|
"""
|
|
Execute the parse expression on the given file or filename.
|
|
If a filename is specified (instead of a file object),
|
|
the entire file is opened, read, and closed before parsing.
|
|
"""
|
|
try:
|
|
file_contents = file_or_filename.read()
|
|
except AttributeError:
|
|
with open(file_or_filename, "r") as f:
|
|
file_contents = f.read()
|
|
try:
|
|
return self.parseString(file_contents, parseAll)
|
|
except ParseBaseException as exc:
|
|
if ParserElement.verbose_stacktrace:
|
|
raise
|
|
else:
|
|
# catch and re-raise exception from here, clears out pyparsing internal stack trace
|
|
raise exc
|
|
|
|
def __eq__(self,other):
|
|
if isinstance(other, ParserElement):
|
|
return self is other or vars(self) == vars(other)
|
|
elif isinstance(other, basestring):
|
|
return self.matches(other)
|
|
else:
|
|
return super(ParserElement,self)==other
|
|
|
|
def __ne__(self,other):
|
|
return not (self == other)
|
|
|
|
def __hash__(self):
|
|
return hash(id(self))
|
|
|
|
def __req__(self,other):
|
|
return self == other
|
|
|
|
def __rne__(self,other):
|
|
return not (self == other)
|
|
|
|
def matches(self, testString, parseAll=True):
|
|
"""
|
|
Method for quick testing of a parser against a test string. Good for simple
|
|
inline microtests of sub expressions while building up larger parser.
|
|
|
|
Parameters:
|
|
- testString - to test against this expression for a match
|
|
- parseAll - (default=C{True}) - flag to pass to C{L{parseString}} when running tests
|
|
|
|
Example::
|
|
expr = Word(nums)
|
|
assert expr.matches("100")
|
|
"""
|
|
try:
|
|
self.parseString(_ustr(testString), parseAll=parseAll)
|
|
return True
|
|
except ParseBaseException:
|
|
return False
|
|
|
|
def runTests(self, tests, parseAll=True, comment='#', fullDump=True, printResults=True, failureTests=False):
|
|
"""
|
|
Execute the parse expression on a series of test strings, showing each
|
|
test, the parsed results or where the parse failed. Quick and easy way to
|
|
run a parse expression against a list of sample strings.
|
|
|
|
Parameters:
|
|
- tests - a list of separate test strings, or a multiline string of test strings
|
|
- parseAll - (default=C{True}) - flag to pass to C{L{parseString}} when running tests
|
|
- comment - (default=C{'#'}) - expression for indicating embedded comments in the test
|
|
string; pass None to disable comment filtering
|
|
- fullDump - (default=C{True}) - dump results as list followed by results names in nested outline;
|
|
if False, only dump nested list
|
|
- printResults - (default=C{True}) prints test output to stdout
|
|
- failureTests - (default=C{False}) indicates if these tests are expected to fail parsing
|
|
|
|
Returns: a (success, results) tuple, where success indicates that all tests succeeded
|
|
(or failed if C{failureTests} is True), and the results contain a list of lines of each
|
|
test's output
|
|
|
|
Example::
|
|
number_expr = pyparsing_common.number.copy()
|
|
|
|
result = number_expr.runTests('''
|
|
# unsigned integer
|
|
100
|
|
# negative integer
|
|
-100
|
|
# float with scientific notation
|
|
6.02e23
|
|
# integer with scientific notation
|
|
1e-12
|
|
''')
|
|
print("Success" if result[0] else "Failed!")
|
|
|
|
result = number_expr.runTests('''
|
|
# stray character
|
|
100Z
|
|
# missing leading digit before '.'
|
|
-.100
|
|
# too many '.'
|
|
3.14.159
|
|
''', failureTests=True)
|
|
print("Success" if result[0] else "Failed!")
|
|
prints::
|
|
# unsigned integer
|
|
100
|
|
[100]
|
|
|
|
# negative integer
|
|
-100
|
|
[-100]
|
|
|
|
# float with scientific notation
|
|
6.02e23
|
|
[6.02e+23]
|
|
|
|
# integer with scientific notation
|
|
1e-12
|
|
[1e-12]
|
|
|
|
Success
|
|
|
|
# stray character
|
|
100Z
|
|
^
|
|
FAIL: Expected end of text (at char 3), (line:1, col:4)
|
|
|
|
# missing leading digit before '.'
|
|
-.100
|
|
^
|
|
FAIL: Expected {real number with scientific notation | real number | signed integer} (at char 0), (line:1, col:1)
|
|
|
|
# too many '.'
|
|
3.14.159
|
|
^
|
|
FAIL: Expected end of text (at char 4), (line:1, col:5)
|
|
|
|
Success
|
|
|
|
Each test string must be on a single line. If you want to test a string that spans multiple
|
|
lines, create a test like this::
|
|
|
|
expr.runTest(r"this is a test\\n of strings that spans \\n 3 lines")
|
|
|
|
(Note that this is a raw string literal, you must include the leading 'r'.)
|
|
"""
|
|
if isinstance(tests, basestring):
|
|
tests = list(map(str.strip, tests.rstrip().splitlines()))
|
|
if isinstance(comment, basestring):
|
|
comment = Literal(comment)
|
|
allResults = []
|
|
comments = []
|
|
success = True
|
|
for t in tests:
|
|
if comment is not None and comment.matches(t, False) or comments and not t:
|
|
comments.append(t)
|
|
continue
|
|
if not t:
|
|
continue
|
|
out = ['\n'.join(comments), t]
|
|
comments = []
|
|
try:
|
|
t = t.replace(r'\n','\n')
|
|
result = self.parseString(t, parseAll=parseAll)
|
|
out.append(result.dump(full=fullDump))
|
|
success = success and not failureTests
|
|
except ParseBaseException as pe:
|
|
fatal = "(FATAL)" if isinstance(pe, ParseFatalException) else ""
|
|
if '\n' in t:
|
|
out.append(line(pe.loc, t))
|
|
out.append(' '*(col(pe.loc,t)-1) + '^' + fatal)
|
|
else:
|
|
out.append(' '*pe.loc + '^' + fatal)
|
|
out.append("FAIL: " + str(pe))
|
|
success = success and failureTests
|
|
result = pe
|
|
except Exception as exc:
|
|
out.append("FAIL-EXCEPTION: " + str(exc))
|
|
success = success and failureTests
|
|
result = exc
|
|
|
|
if printResults:
|
|
if fullDump:
|
|
out.append('')
|
|
print('\n'.join(out))
|
|
|
|
allResults.append((t, result))
|
|
|
|
return success, allResults
|
|
|
|
|
|
class Token(ParserElement):
|
|
"""
|
|
Abstract C{ParserElement} subclass, for defining atomic matching patterns.
|
|
"""
|
|
def __init__( self ):
|
|
super(Token,self).__init__( savelist=False )
|
|
|
|
|
|
class Empty(Token):
|
|
"""
|
|
An empty token, will always match.
|
|
"""
|
|
def __init__( self ):
|
|
super(Empty,self).__init__()
|
|
self.name = "Empty"
|
|
self.mayReturnEmpty = True
|
|
self.mayIndexError = False
|
|
|
|
|
|
class NoMatch(Token):
|
|
"""
|
|
A token that will never match.
|
|
"""
|
|
def __init__( self ):
|
|
super(NoMatch,self).__init__()
|
|
self.name = "NoMatch"
|
|
self.mayReturnEmpty = True
|
|
self.mayIndexError = False
|
|
self.errmsg = "Unmatchable token"
|
|
|
|
def parseImpl( self, instring, loc, doActions=True ):
|
|
raise ParseException(instring, loc, self.errmsg, self)
|
|
|
|
|
|
class Literal(Token):
|
|
"""
|
|
Token to exactly match a specified string.
|
|
|
|
Example::
|
|
Literal('blah').parseString('blah') # -> ['blah']
|
|
Literal('blah').parseString('blahfooblah') # -> ['blah']
|
|
Literal('blah').parseString('bla') # -> Exception: Expected "blah"
|
|
|
|
For case-insensitive matching, use L{CaselessLiteral}.
|
|
|
|
For keyword matching (force word break before and after the matched string),
|
|
use L{Keyword} or L{CaselessKeyword}.
|
|
"""
|
|
def __init__( self, matchString ):
|
|
super(Literal,self).__init__()
|
|
self.match = matchString
|
|
self.matchLen = len(matchString)
|
|
try:
|
|
self.firstMatchChar = matchString[0]
|
|
except IndexError:
|
|
warnings.warn("null string passed to Literal; use Empty() instead",
|
|
SyntaxWarning, stacklevel=2)
|
|
self.__class__ = Empty
|
|
self.name = '"%s"' % _ustr(self.match)
|
|
self.errmsg = "Expected " + self.name
|
|
self.mayReturnEmpty = False
|
|
self.mayIndexError = False
|
|
|
|
# Performance tuning: this routine gets called a *lot*
|
|
# if this is a single character match string and the first character matches,
|
|
# short-circuit as quickly as possible, and avoid calling startswith
|
|
#~ @profile
|
|
def parseImpl( self, instring, loc, doActions=True ):
|
|
if (instring[loc] == self.firstMatchChar and
|
|
(self.matchLen==1 or instring.startswith(self.match,loc)) ):
|
|
return loc+self.matchLen, self.match
|
|
raise ParseException(instring, loc, self.errmsg, self)
|
|
_L = Literal
|
|
ParserElement._literalStringClass = Literal
|
|
|
|
class Keyword(Token):
|
|
"""
|
|
Token to exactly match a specified string as a keyword, that is, it must be
|
|
immediately followed by a non-keyword character. Compare with C{L{Literal}}:
|
|
- C{Literal("if")} will match the leading C{'if'} in C{'ifAndOnlyIf'}.
|
|
- C{Keyword("if")} will not; it will only match the leading C{'if'} in C{'if x=1'}, or C{'if(y==2)'}
|
|
Accepts two optional constructor arguments in addition to the keyword string:
|
|
- C{identChars} is a string of characters that would be valid identifier characters,
|
|
defaulting to all alphanumerics + "_" and "$"
|
|
- C{caseless} allows case-insensitive matching, default is C{False}.
|
|
|
|
Example::
|
|
Keyword("start").parseString("start") # -> ['start']
|
|
Keyword("start").parseString("starting") # -> Exception
|
|
|
|
For case-insensitive matching, use L{CaselessKeyword}.
|
|
"""
|
|
DEFAULT_KEYWORD_CHARS = alphanums+"_$"
|
|
|
|
def __init__( self, matchString, identChars=None, caseless=False ):
|
|
super(Keyword,self).__init__()
|
|
if identChars is None:
|
|
identChars = Keyword.DEFAULT_KEYWORD_CHARS
|
|
self.match = matchString
|
|
self.matchLen = len(matchString)
|
|
try:
|
|
self.firstMatchChar = matchString[0]
|
|
except IndexError:
|
|
warnings.warn("null string passed to Keyword; use Empty() instead",
|
|
SyntaxWarning, stacklevel=2)
|
|
self.name = '"%s"' % self.match
|
|
self.errmsg = "Expected " + self.name
|
|
self.mayReturnEmpty = False
|
|
self.mayIndexError = False
|
|
self.caseless = caseless
|
|
if caseless:
|
|
self.caselessmatch = matchString.upper()
|
|
identChars = identChars.upper()
|
|
self.identChars = set(identChars)
|
|
|
|
def parseImpl( self, instring, loc, doActions=True ):
|
|
if self.caseless:
|
|
if ( (instring[ loc:loc+self.matchLen ].upper() == self.caselessmatch) and
|
|
(loc >= len(instring)-self.matchLen or instring[loc+self.matchLen].upper() not in self.identChars) and
|
|
(loc == 0 or instring[loc-1].upper() not in self.identChars) ):
|
|
return loc+self.matchLen, self.match
|
|
else:
|
|
if (instring[loc] == self.firstMatchChar and
|
|
(self.matchLen==1 or instring.startswith(self.match,loc)) and
|
|
(loc >= len(instring)-self.matchLen or instring[loc+self.matchLen] not in self.identChars) and
|
|
(loc == 0 or instring[loc-1] not in self.identChars) ):
|
|
return loc+self.matchLen, self.match
|
|
raise ParseException(instring, loc, self.errmsg, self)
|
|
|
|
def copy(self):
|
|
c = super(Keyword,self).copy()
|
|
c.identChars = Keyword.DEFAULT_KEYWORD_CHARS
|
|
return c
|
|
|
|
@staticmethod
|
|
def setDefaultKeywordChars( chars ):
|
|
"""Overrides the default Keyword chars
|
|
"""
|
|
Keyword.DEFAULT_KEYWORD_CHARS = chars
|
|
|
|
class CaselessLiteral(Literal):
|
|
"""
|
|
Token to match a specified string, ignoring case of letters.
|
|
Note: the matched results will always be in the case of the given
|
|
match string, NOT the case of the input text.
|
|
|
|
Example::
|
|
OneOrMore(CaselessLiteral("CMD")).parseString("cmd CMD Cmd10") # -> ['CMD', 'CMD', 'CMD']
|
|
|
|
(Contrast with example for L{CaselessKeyword}.)
|
|
"""
|
|
def __init__( self, matchString ):
|
|
super(CaselessLiteral,self).__init__( matchString.upper() )
|
|
# Preserve the defining literal.
|
|
self.returnString = matchString
|
|
self.name = "'%s'" % self.returnString
|
|
self.errmsg = "Expected " + self.name
|
|
|
|
def parseImpl( self, instring, loc, doActions=True ):
|
|
if instring[ loc:loc+self.matchLen ].upper() == self.match:
|
|
return loc+self.matchLen, self.returnString
|
|
raise ParseException(instring, loc, self.errmsg, self)
|
|
|
|
class CaselessKeyword(Keyword):
|
|
"""
|
|
Caseless version of L{Keyword}.
|
|
|
|
Example::
|
|
OneOrMore(CaselessKeyword("CMD")).parseString("cmd CMD Cmd10") # -> ['CMD', 'CMD']
|
|
|
|
(Contrast with example for L{CaselessLiteral}.)
|
|
"""
|
|
def __init__( self, matchString, identChars=None ):
|
|
super(CaselessKeyword,self).__init__( matchString, identChars, caseless=True )
|
|
|
|
def parseImpl( self, instring, loc, doActions=True ):
|
|
if ( (instring[ loc:loc+self.matchLen ].upper() == self.caselessmatch) and
|
|
(loc >= len(instring)-self.matchLen or instring[loc+self.matchLen].upper() not in self.identChars) ):
|
|
return loc+self.matchLen, self.match
|
|
raise ParseException(instring, loc, self.errmsg, self)
|
|
|
|
class CloseMatch(Token):
|
|
"""
|
|
A variation on L{Literal} which matches "close" matches, that is,
|
|
strings with at most 'n' mismatching characters. C{CloseMatch} takes parameters:
|
|
- C{match_string} - string to be matched
|
|
- C{maxMismatches} - (C{default=1}) maximum number of mismatches allowed to count as a match
|
|
|
|
The results from a successful parse will contain the matched text from the input string and the following named results:
|
|
- C{mismatches} - a list of the positions within the match_string where mismatches were found
|
|
- C{original} - the original match_string used to compare against the input string
|
|
|
|
If C{mismatches} is an empty list, then the match was an exact match.
|
|
|
|
Example::
|
|
patt = CloseMatch("ATCATCGAATGGA")
|
|
patt.parseString("ATCATCGAAXGGA") # -> (['ATCATCGAAXGGA'], {'mismatches': [[9]], 'original': ['ATCATCGAATGGA']})
|
|
patt.parseString("ATCAXCGAAXGGA") # -> Exception: Expected 'ATCATCGAATGGA' (with up to 1 mismatches) (at char 0), (line:1, col:1)
|
|
|
|
# exact match
|
|
patt.parseString("ATCATCGAATGGA") # -> (['ATCATCGAATGGA'], {'mismatches': [[]], 'original': ['ATCATCGAATGGA']})
|
|
|
|
# close match allowing up to 2 mismatches
|
|
patt = CloseMatch("ATCATCGAATGGA", maxMismatches=2)
|
|
patt.parseString("ATCAXCGAAXGGA") # -> (['ATCAXCGAAXGGA'], {'mismatches': [[4, 9]], 'original': ['ATCATCGAATGGA']})
|
|
"""
|
|
def __init__(self, match_string, maxMismatches=1):
|
|
super(CloseMatch,self).__init__()
|
|
self.name = match_string
|
|
self.match_string = match_string
|
|
self.maxMismatches = maxMismatches
|
|
self.errmsg = "Expected %r (with up to %d mismatches)" % (self.match_string, self.maxMismatches)
|
|
self.mayIndexError = False
|
|
self.mayReturnEmpty = False
|
|
|
|
def parseImpl( self, instring, loc, doActions=True ):
|
|
start = loc
|
|
instrlen = len(instring)
|
|
maxloc = start + len(self.match_string)
|
|
|
|
if maxloc <= instrlen:
|
|
match_string = self.match_string
|
|
match_stringloc = 0
|
|
mismatches = []
|
|
maxMismatches = self.maxMismatches
|
|
|
|
for match_stringloc,s_m in enumerate(zip(instring[loc:maxloc], self.match_string)):
|
|
src,mat = s_m
|
|
if src != mat:
|
|
mismatches.append(match_stringloc)
|
|
if len(mismatches) > maxMismatches:
|
|
break
|
|
else:
|
|
loc = match_stringloc + 1
|
|
results = ParseResults([instring[start:loc]])
|
|
results['original'] = self.match_string
|
|
results['mismatches'] = mismatches
|
|
return loc, results
|
|
|
|
raise ParseException(instring, loc, self.errmsg, self)
|
|
|
|
|
|
class Word(Token):
|
|
"""
|
|
Token for matching words composed of allowed character sets.
|
|
Defined with string containing all allowed initial characters,
|
|
an optional string containing allowed body characters (if omitted,
|
|
defaults to the initial character set), and an optional minimum,
|
|
maximum, and/or exact length. The default value for C{min} is 1 (a
|
|
minimum value < 1 is not valid); the default values for C{max} and C{exact}
|
|
are 0, meaning no maximum or exact length restriction. An optional
|
|
C{excludeChars} parameter can list characters that might be found in
|
|
the input C{bodyChars} string; useful to define a word of all printables
|
|
except for one or two characters, for instance.
|
|
|
|
L{srange} is useful for defining custom character set strings for defining
|
|
C{Word} expressions, using range notation from regular expression character sets.
|
|
|
|
A common mistake is to use C{Word} to match a specific literal string, as in
|
|
C{Word("Address")}. Remember that C{Word} uses the string argument to define
|
|
I{sets} of matchable characters. This expression would match "Add", "AAA",
|
|
"dAred", or any other word made up of the characters 'A', 'd', 'r', 'e', and 's'.
|
|
To match an exact literal string, use L{Literal} or L{Keyword}.
|
|
|
|
pyparsing includes helper strings for building Words:
|
|
- L{alphas}
|
|
- L{nums}
|
|
- L{alphanums}
|
|
- L{hexnums}
|
|
- L{alphas8bit} (alphabetic characters in ASCII range 128-255 - accented, tilded, umlauted, etc.)
|
|
- L{punc8bit} (non-alphabetic characters in ASCII range 128-255 - currency, symbols, superscripts, diacriticals, etc.)
|
|
- L{printables} (any non-whitespace character)
|
|
|
|
Example::
|
|
# a word composed of digits
|
|
integer = Word(nums) # equivalent to Word("0123456789") or Word(srange("0-9"))
|
|
|
|
# a word with a leading capital, and zero or more lowercase
|
|
capital_word = Word(alphas.upper(), alphas.lower())
|
|
|
|
# hostnames are alphanumeric, with leading alpha, and '-'
|
|
hostname = Word(alphas, alphanums+'-')
|
|
|
|
# roman numeral (not a strict parser, accepts invalid mix of characters)
|
|
roman = Word("IVXLCDM")
|
|
|
|
# any string of non-whitespace characters, except for ','
|
|
csv_value = Word(printables, excludeChars=",")
|
|
"""
|
|
def __init__( self, initChars, bodyChars=None, min=1, max=0, exact=0, asKeyword=False, excludeChars=None ):
|
|
super(Word,self).__init__()
|
|
if excludeChars:
|
|
initChars = ''.join(c for c in initChars if c not in excludeChars)
|
|
if bodyChars:
|
|
bodyChars = ''.join(c for c in bodyChars if c not in excludeChars)
|
|
self.initCharsOrig = initChars
|
|
self.initChars = set(initChars)
|
|
if bodyChars :
|
|
self.bodyCharsOrig = bodyChars
|
|
self.bodyChars = set(bodyChars)
|
|
else:
|
|
self.bodyCharsOrig = initChars
|
|
self.bodyChars = set(initChars)
|
|
|
|
self.maxSpecified = max > 0
|
|
|
|
if min < 1:
|
|
raise ValueError("cannot specify a minimum length < 1; use Optional(Word()) if zero-length word is permitted")
|
|
|
|
self.minLen = min
|
|
|
|
if max > 0:
|
|
self.maxLen = max
|
|
else:
|
|
self.maxLen = _MAX_INT
|
|
|
|
if exact > 0:
|
|
self.maxLen = exact
|
|
self.minLen = exact
|
|
|
|
self.name = _ustr(self)
|
|
self.errmsg = "Expected " + self.name
|
|
self.mayIndexError = False
|
|
self.asKeyword = asKeyword
|
|
|
|
if ' ' not in self.initCharsOrig+self.bodyCharsOrig and (min==1 and max==0 and exact==0):
|
|
if self.bodyCharsOrig == self.initCharsOrig:
|
|
self.reString = "[%s]+" % _escapeRegexRangeChars(self.initCharsOrig)
|
|
elif len(self.initCharsOrig) == 1:
|
|
self.reString = "%s[%s]*" % \
|
|
(re.escape(self.initCharsOrig),
|
|
_escapeRegexRangeChars(self.bodyCharsOrig),)
|
|
else:
|
|
self.reString = "[%s][%s]*" % \
|
|
(_escapeRegexRangeChars(self.initCharsOrig),
|
|
_escapeRegexRangeChars(self.bodyCharsOrig),)
|
|
if self.asKeyword:
|
|
self.reString = r"\b"+self.reString+r"\b"
|
|
try:
|
|
self.re = re.compile( self.reString )
|
|
except Exception:
|
|
self.re = None
|
|
|
|
def parseImpl( self, instring, loc, doActions=True ):
|
|
if self.re:
|
|
result = self.re.match(instring,loc)
|
|
if not result:
|
|
raise ParseException(instring, loc, self.errmsg, self)
|
|
|
|
loc = result.end()
|
|
return loc, result.group()
|
|
|
|
if not(instring[ loc ] in self.initChars):
|
|
raise ParseException(instring, loc, self.errmsg, self)
|
|
|
|
start = loc
|
|
loc += 1
|
|
instrlen = len(instring)
|
|
bodychars = self.bodyChars
|
|
maxloc = start + self.maxLen
|
|
maxloc = min( maxloc, instrlen )
|
|
while loc < maxloc and instring[loc] in bodychars:
|
|
loc += 1
|
|
|
|
throwException = False
|
|
if loc - start < self.minLen:
|
|
throwException = True
|
|
if self.maxSpecified and loc < instrlen and instring[loc] in bodychars:
|
|
throwException = True
|
|
if self.asKeyword:
|
|
if (start>0 and instring[start-1] in bodychars) or (loc<instrlen and instring[loc] in bodychars):
|
|
throwException = True
|
|
|
|
if throwException:
|
|
raise ParseException(instring, loc, self.errmsg, self)
|
|
|
|
return loc, instring[start:loc]
|
|
|
|
def __str__( self ):
|
|
try:
|
|
return super(Word,self).__str__()
|
|
except Exception:
|
|
pass
|
|
|
|
|
|
if self.strRepr is None:
|
|
|
|
def charsAsStr(s):
|
|
if len(s)>4:
|
|
return s[:4]+"..."
|
|
else:
|
|
return s
|
|
|
|
if ( self.initCharsOrig != self.bodyCharsOrig ):
|
|
self.strRepr = "W:(%s,%s)" % ( charsAsStr(self.initCharsOrig), charsAsStr(self.bodyCharsOrig) )
|
|
else:
|
|
self.strRepr = "W:(%s)" % charsAsStr(self.initCharsOrig)
|
|
|
|
return self.strRepr
|
|
|
|
|
|
class Regex(Token):
|
|
r"""
|
|
Token for matching strings that match a given regular expression.
|
|
Defined with string specifying the regular expression in a form recognized by the inbuilt Python re module.
|
|
If the given regex contains named groups (defined using C{(?P<name>...)}), these will be preserved as
|
|
named parse results.
|
|
|
|
Example::
|
|
realnum = Regex(r"[+-]?\d+\.\d*")
|
|
date = Regex(r'(?P<year>\d{4})-(?P<month>\d\d?)-(?P<day>\d\d?)')
|
|
# ref: http://stackoverflow.com/questions/267399/how-do-you-match-only-valid-roman-numerals-with-a-regular-expression
|
|
roman = Regex(r"M{0,4}(CM|CD|D?C{0,3})(XC|XL|L?X{0,3})(IX|IV|V?I{0,3})")
|
|
"""
|
|
compiledREtype = type(re.compile("[A-Z]"))
|
|
def __init__( self, pattern, flags=0):
|
|
"""The parameters C{pattern} and C{flags} are passed to the C{re.compile()} function as-is. See the Python C{re} module for an explanation of the acceptable patterns and flags."""
|
|
super(Regex,self).__init__()
|
|
|
|
if isinstance(pattern, basestring):
|
|
if not pattern:
|
|
warnings.warn("null string passed to Regex; use Empty() instead",
|
|
SyntaxWarning, stacklevel=2)
|
|
|
|
self.pattern = pattern
|
|
self.flags = flags
|
|
|
|
try:
|
|
self.re = re.compile(self.pattern, self.flags)
|
|
self.reString = self.pattern
|
|
except sre_constants.error:
|
|
warnings.warn("invalid pattern (%s) passed to Regex" % pattern,
|
|
SyntaxWarning, stacklevel=2)
|
|
raise
|
|
|
|
elif isinstance(pattern, Regex.compiledREtype):
|
|
self.re = pattern
|
|
self.pattern = \
|
|
self.reString = str(pattern)
|
|
self.flags = flags
|
|
|
|
else:
|
|
raise ValueError("Regex may only be constructed with a string or a compiled RE object")
|
|
|
|
self.name = _ustr(self)
|
|
self.errmsg = "Expected " + self.name
|
|
self.mayIndexError = False
|
|
self.mayReturnEmpty = True
|
|
|
|
def parseImpl( self, instring, loc, doActions=True ):
|
|
result = self.re.match(instring,loc)
|
|
if not result:
|
|
raise ParseException(instring, loc, self.errmsg, self)
|
|
|
|
loc = result.end()
|
|
d = result.groupdict()
|
|
ret = ParseResults(result.group())
|
|
if d:
|
|
for k in d:
|
|
ret[k] = d[k]
|
|
return loc,ret
|
|
|
|
def __str__( self ):
|
|
try:
|
|
return super(Regex,self).__str__()
|
|
except Exception:
|
|
pass
|
|
|
|
if self.strRepr is None:
|
|
self.strRepr = "Re:(%s)" % repr(self.pattern)
|
|
|
|
return self.strRepr
|
|
|
|
|
|
class QuotedString(Token):
|
|
r"""
|
|
Token for matching strings that are delimited by quoting characters.
|
|
|
|
Defined with the following parameters:
|
|
- quoteChar - string of one or more characters defining the quote delimiting string
|
|
- escChar - character to escape quotes, typically backslash (default=C{None})
|
|
- escQuote - special quote sequence to escape an embedded quote string (such as SQL's "" to escape an embedded ") (default=C{None})
|
|
- multiline - boolean indicating whether quotes can span multiple lines (default=C{False})
|
|
- unquoteResults - boolean indicating whether the matched text should be unquoted (default=C{True})
|
|
- endQuoteChar - string of one or more characters defining the end of the quote delimited string (default=C{None} => same as quoteChar)
|
|
- convertWhitespaceEscapes - convert escaped whitespace (C{'\t'}, C{'\n'}, etc.) to actual whitespace (default=C{True})
|
|
|
|
Example::
|
|
qs = QuotedString('"')
|
|
print(qs.searchString('lsjdf "This is the quote" sldjf'))
|
|
complex_qs = QuotedString('{{', endQuoteChar='}}')
|
|
print(complex_qs.searchString('lsjdf {{This is the "quote"}} sldjf'))
|
|
sql_qs = QuotedString('"', escQuote='""')
|
|
print(sql_qs.searchString('lsjdf "This is the quote with ""embedded"" quotes" sldjf'))
|
|
prints::
|
|
[['This is the quote']]
|
|
[['This is the "quote"']]
|
|
[['This is the quote with "embedded" quotes']]
|
|
"""
|
|
def __init__( self, quoteChar, escChar=None, escQuote=None, multiline=False, unquoteResults=True, endQuoteChar=None, convertWhitespaceEscapes=True):
|
|
super(QuotedString,self).__init__()
|
|
|
|
# remove white space from quote chars - wont work anyway
|
|
quoteChar = quoteChar.strip()
|
|
if not quoteChar:
|
|
warnings.warn("quoteChar cannot be the empty string",SyntaxWarning,stacklevel=2)
|
|
raise SyntaxError()
|
|
|
|
if endQuoteChar is None:
|
|
endQuoteChar = quoteChar
|
|
else:
|
|
endQuoteChar = endQuoteChar.strip()
|
|
if not endQuoteChar:
|
|
warnings.warn("endQuoteChar cannot be the empty string",SyntaxWarning,stacklevel=2)
|
|
raise SyntaxError()
|
|
|
|
self.quoteChar = quoteChar
|
|
self.quoteCharLen = len(quoteChar)
|
|
self.firstQuoteChar = quoteChar[0]
|
|
self.endQuoteChar = endQuoteChar
|
|
self.endQuoteCharLen = len(endQuoteChar)
|
|
self.escChar = escChar
|
|
self.escQuote = escQuote
|
|
self.unquoteResults = unquoteResults
|
|
self.convertWhitespaceEscapes = convertWhitespaceEscapes
|
|
|
|
if multiline:
|
|
self.flags = re.MULTILINE | re.DOTALL
|
|
self.pattern = r'%s(?:[^%s%s]' % \
|
|
( re.escape(self.quoteChar),
|
|
_escapeRegexRangeChars(self.endQuoteChar[0]),
|
|
(escChar is not None and _escapeRegexRangeChars(escChar) or '') )
|
|
else:
|
|
self.flags = 0
|
|
self.pattern = r'%s(?:[^%s\n\r%s]' % \
|
|
( re.escape(self.quoteChar),
|
|
_escapeRegexRangeChars(self.endQuoteChar[0]),
|
|
(escChar is not None and _escapeRegexRangeChars(escChar) or '') )
|
|
if len(self.endQuoteChar) > 1:
|
|
self.pattern += (
|
|
'|(?:' + ')|(?:'.join("%s[^%s]" % (re.escape(self.endQuoteChar[:i]),
|
|
_escapeRegexRangeChars(self.endQuoteChar[i]))
|
|
for i in range(len(self.endQuoteChar)-1,0,-1)) + ')'
|
|
)
|
|
if escQuote:
|
|
self.pattern += (r'|(?:%s)' % re.escape(escQuote))
|
|
if escChar:
|
|
self.pattern += (r'|(?:%s.)' % re.escape(escChar))
|
|
self.escCharReplacePattern = re.escape(self.escChar)+"(.)"
|
|
self.pattern += (r')*%s' % re.escape(self.endQuoteChar))
|
|
|
|
try:
|
|
self.re = re.compile(self.pattern, self.flags)
|
|
self.reString = self.pattern
|
|
except sre_constants.error:
|
|
warnings.warn("invalid pattern (%s) passed to Regex" % self.pattern,
|
|
SyntaxWarning, stacklevel=2)
|
|
raise
|
|
|
|
self.name = _ustr(self)
|
|
self.errmsg = "Expected " + self.name
|
|
self.mayIndexError = False
|
|
self.mayReturnEmpty = True
|
|
|
|
def parseImpl( self, instring, loc, doActions=True ):
|
|
result = instring[loc] == self.firstQuoteChar and self.re.match(instring,loc) or None
|
|
if not result:
|
|
raise ParseException(instring, loc, self.errmsg, self)
|
|
|
|
loc = result.end()
|
|
ret = result.group()
|
|
|
|
if self.unquoteResults:
|
|
|
|
# strip off quotes
|
|
ret = ret[self.quoteCharLen:-self.endQuoteCharLen]
|
|
|
|
if isinstance(ret,basestring):
|
|
# replace escaped whitespace
|
|
if '\\' in ret and self.convertWhitespaceEscapes:
|
|
ws_map = {
|
|
r'\t' : '\t',
|
|
r'\n' : '\n',
|
|
r'\f' : '\f',
|
|
r'\r' : '\r',
|
|
}
|
|
for wslit,wschar in ws_map.items():
|
|
ret = ret.replace(wslit, wschar)
|
|
|
|
# replace escaped characters
|
|
if self.escChar:
|
|
ret = re.sub(self.escCharReplacePattern, r"\g<1>", ret)
|
|
|
|
# replace escaped quotes
|
|
if self.escQuote:
|
|
ret = ret.replace(self.escQuote, self.endQuoteChar)
|
|
|
|
return loc, ret
|
|
|
|
def __str__( self ):
|
|
try:
|
|
return super(QuotedString,self).__str__()
|
|
except Exception:
|
|
pass
|
|
|
|
if self.strRepr is None:
|
|
self.strRepr = "quoted string, starting with %s ending with %s" % (self.quoteChar, self.endQuoteChar)
|
|
|
|
return self.strRepr
|
|
|
|
|
|
class CharsNotIn(Token):
|
|
"""
|
|
Token for matching words composed of characters I{not} in a given set (will
|
|
include whitespace in matched characters if not listed in the provided exclusion set - see example).
|
|
Defined with string containing all disallowed characters, and an optional
|
|
minimum, maximum, and/or exact length. The default value for C{min} is 1 (a
|
|
minimum value < 1 is not valid); the default values for C{max} and C{exact}
|
|
are 0, meaning no maximum or exact length restriction.
|
|
|
|
Example::
|
|
# define a comma-separated-value as anything that is not a ','
|
|
csv_value = CharsNotIn(',')
|
|
print(delimitedList(csv_value).parseString("dkls,lsdkjf,s12 34,@!#,213"))
|
|
prints::
|
|
['dkls', 'lsdkjf', 's12 34', '@!#', '213']
|
|
"""
|
|
def __init__( self, notChars, min=1, max=0, exact=0 ):
|
|
super(CharsNotIn,self).__init__()
|
|
self.skipWhitespace = False
|
|
self.notChars = notChars
|
|
|
|
if min < 1:
|
|
raise ValueError("cannot specify a minimum length < 1; use Optional(CharsNotIn()) if zero-length char group is permitted")
|
|
|
|
self.minLen = min
|
|
|
|
if max > 0:
|
|
self.maxLen = max
|
|
else:
|
|
self.maxLen = _MAX_INT
|
|
|
|
if exact > 0:
|
|
self.maxLen = exact
|
|
self.minLen = exact
|
|
|
|
self.name = _ustr(self)
|
|
self.errmsg = "Expected " + self.name
|
|
self.mayReturnEmpty = ( self.minLen == 0 )
|
|
self.mayIndexError = False
|
|
|
|
def parseImpl( self, instring, loc, doActions=True ):
|
|
if instring[loc] in self.notChars:
|
|
raise ParseException(instring, loc, self.errmsg, self)
|
|
|
|
start = loc
|
|
loc += 1
|
|
notchars = self.notChars
|
|
maxlen = min( start+self.maxLen, len(instring) )
|
|
while loc < maxlen and \
|
|
(instring[loc] not in notchars):
|
|
loc += 1
|
|
|
|
if loc - start < self.minLen:
|
|
raise ParseException(instring, loc, self.errmsg, self)
|
|
|
|
return loc, instring[start:loc]
|
|
|
|
def __str__( self ):
|
|
try:
|
|
return super(CharsNotIn, self).__str__()
|
|
except Exception:
|
|
pass
|
|
|
|
if self.strRepr is None:
|
|
if len(self.notChars) > 4:
|
|
self.strRepr = "!W:(%s...)" % self.notChars[:4]
|
|
else:
|
|
self.strRepr = "!W:(%s)" % self.notChars
|
|
|
|
return self.strRepr
|
|
|
|
class White(Token):
|
|
"""
|
|
Special matching class for matching whitespace. Normally, whitespace is ignored
|
|
by pyparsing grammars. This class is included when some whitespace structures
|
|
are significant. Define with a string containing the whitespace characters to be
|
|
matched; default is C{" \\t\\r\\n"}. Also takes optional C{min}, C{max}, and C{exact} arguments,
|
|
as defined for the C{L{Word}} class.
|
|
"""
|
|
whiteStrs = {
|
|
" " : "<SPC>",
|
|
"\t": "<TAB>",
|
|
"\n": "<LF>",
|
|
"\r": "<CR>",
|
|
"\f": "<FF>",
|
|
}
|
|
def __init__(self, ws=" \t\r\n", min=1, max=0, exact=0):
|
|
super(White,self).__init__()
|
|
self.matchWhite = ws
|
|
self.setWhitespaceChars( "".join(c for c in self.whiteChars if c not in self.matchWhite) )
|
|
#~ self.leaveWhitespace()
|
|
self.name = ("".join(White.whiteStrs[c] for c in self.matchWhite))
|
|
self.mayReturnEmpty = True
|
|
self.errmsg = "Expected " + self.name
|
|
|
|
self.minLen = min
|
|
|
|
if max > 0:
|
|
self.maxLen = max
|
|
else:
|
|
self.maxLen = _MAX_INT
|
|
|
|
if exact > 0:
|
|
self.maxLen = exact
|
|
self.minLen = exact
|
|
|
|
def parseImpl( self, instring, loc, doActions=True ):
|
|
if not(instring[ loc ] in self.matchWhite):
|
|
raise ParseException(instring, loc, self.errmsg, self)
|
|
start = loc
|
|
loc += 1
|
|
maxloc = start + self.maxLen
|
|
maxloc = min( maxloc, len(instring) )
|
|
while loc < maxloc and instring[loc] in self.matchWhite:
|
|
loc += 1
|
|
|
|
if loc - start < self.minLen:
|
|
raise ParseException(instring, loc, self.errmsg, self)
|
|
|
|
return loc, instring[start:loc]
|
|
|
|
|
|
class _PositionToken(Token):
|
|
def __init__( self ):
|
|
super(_PositionToken,self).__init__()
|
|
self.name=self.__class__.__name__
|
|
self.mayReturnEmpty = True
|
|
self.mayIndexError = False
|
|
|
|
class GoToColumn(_PositionToken):
|
|
"""
|
|
Token to advance to a specific column of input text; useful for tabular report scraping.
|
|
"""
|
|
def __init__( self, colno ):
|
|
super(GoToColumn,self).__init__()
|
|
self.col = colno
|
|
|
|
def preParse( self, instring, loc ):
|
|
if col(loc,instring) != self.col:
|
|
instrlen = len(instring)
|
|
if self.ignoreExprs:
|
|
loc = self._skipIgnorables( instring, loc )
|
|
while loc < instrlen and instring[loc].isspace() and col( loc, instring ) != self.col :
|
|
loc += 1
|
|
return loc
|
|
|
|
def parseImpl( self, instring, loc, doActions=True ):
|
|
thiscol = col( loc, instring )
|
|
if thiscol > self.col:
|
|
raise ParseException( instring, loc, "Text not in expected column", self )
|
|
newloc = loc + self.col - thiscol
|
|
ret = instring[ loc: newloc ]
|
|
return newloc, ret
|
|
|
|
|
|
class LineStart(_PositionToken):
|
|
"""
|
|
Matches if current position is at the beginning of a line within the parse string
|
|
|
|
Example::
|
|
|
|
test = '''\
|
|
AAA this line
|
|
AAA and this line
|
|
AAA but not this one
|
|
B AAA and definitely not this one
|
|
'''
|
|
|
|
for t in (LineStart() + 'AAA' + restOfLine).searchString(test):
|
|
print(t)
|
|
|
|
Prints::
|
|
['AAA', ' this line']
|
|
['AAA', ' and this line']
|
|
|
|
"""
|
|
def __init__( self ):
|
|
super(LineStart,self).__init__()
|
|
self.errmsg = "Expected start of line"
|
|
|
|
def parseImpl( self, instring, loc, doActions=True ):
|
|
if col(loc, instring) == 1:
|
|
return loc, []
|
|
raise ParseException(instring, loc, self.errmsg, self)
|
|
|
|
class LineEnd(_PositionToken):
|
|
"""
|
|
Matches if current position is at the end of a line within the parse string
|
|
"""
|
|
def __init__( self ):
|
|
super(LineEnd,self).__init__()
|
|
self.setWhitespaceChars( ParserElement.DEFAULT_WHITE_CHARS.replace("\n","") )
|
|
self.errmsg = "Expected end of line"
|
|
|
|
def parseImpl( self, instring, loc, doActions=True ):
|
|
if loc<len(instring):
|
|
if instring[loc] == "\n":
|
|
return loc+1, "\n"
|
|
else:
|
|
raise ParseException(instring, loc, self.errmsg, self)
|
|
elif loc == len(instring):
|
|
return loc+1, []
|
|
else:
|
|
raise ParseException(instring, loc, self.errmsg, self)
|
|
|
|
class StringStart(_PositionToken):
|
|
"""
|
|
Matches if current position is at the beginning of the parse string
|
|
"""
|
|
def __init__( self ):
|
|
super(StringStart,self).__init__()
|
|
self.errmsg = "Expected start of text"
|
|
|
|
def parseImpl( self, instring, loc, doActions=True ):
|
|
if loc != 0:
|
|
# see if entire string up to here is just whitespace and ignoreables
|
|
if loc != self.preParse( instring, 0 ):
|
|
raise ParseException(instring, loc, self.errmsg, self)
|
|
return loc, []
|
|
|
|
class StringEnd(_PositionToken):
|
|
"""
|
|
Matches if current position is at the end of the parse string
|
|
"""
|
|
def __init__( self ):
|
|
super(StringEnd,self).__init__()
|
|
self.errmsg = "Expected end of text"
|
|
|
|
def parseImpl( self, instring, loc, doActions=True ):
|
|
if loc < len(instring):
|
|
raise ParseException(instring, loc, self.errmsg, self)
|
|
elif loc == len(instring):
|
|
return loc+1, []
|
|
elif loc > len(instring):
|
|
return loc, []
|
|
else:
|
|
raise ParseException(instring, loc, self.errmsg, self)
|
|
|
|
class WordStart(_PositionToken):
|
|
"""
|
|
Matches if the current position is at the beginning of a Word, and
|
|
is not preceded by any character in a given set of C{wordChars}
|
|
(default=C{printables}). To emulate the C{\b} behavior of regular expressions,
|
|
use C{WordStart(alphanums)}. C{WordStart} will also match at the beginning of
|
|
the string being parsed, or at the beginning of a line.
|
|
"""
|
|
def __init__(self, wordChars = printables):
|
|
super(WordStart,self).__init__()
|
|
self.wordChars = set(wordChars)
|
|
self.errmsg = "Not at the start of a word"
|
|
|
|
def parseImpl(self, instring, loc, doActions=True ):
|
|
if loc != 0:
|
|
if (instring[loc-1] in self.wordChars or
|
|
instring[loc] not in self.wordChars):
|
|
raise ParseException(instring, loc, self.errmsg, self)
|
|
return loc, []
|
|
|
|
class WordEnd(_PositionToken):
|
|
"""
|
|
Matches if the current position is at the end of a Word, and
|
|
is not followed by any character in a given set of C{wordChars}
|
|
(default=C{printables}). To emulate the C{\b} behavior of regular expressions,
|
|
use C{WordEnd(alphanums)}. C{WordEnd} will also match at the end of
|
|
the string being parsed, or at the end of a line.
|
|
"""
|
|
def __init__(self, wordChars = printables):
|
|
super(WordEnd,self).__init__()
|
|
self.wordChars = set(wordChars)
|
|
self.skipWhitespace = False
|
|
self.errmsg = "Not at the end of a word"
|
|
|
|
def parseImpl(self, instring, loc, doActions=True ):
|
|
instrlen = len(instring)
|
|
if instrlen>0 and loc<instrlen:
|
|
if (instring[loc] in self.wordChars or
|
|
instring[loc-1] not in self.wordChars):
|
|
raise ParseException(instring, loc, self.errmsg, self)
|
|
return loc, []
|
|
|
|
|
|
class ParseExpression(ParserElement):
|
|
"""
|
|
Abstract subclass of ParserElement, for combining and post-processing parsed tokens.
|
|
"""
|
|
def __init__( self, exprs, savelist = False ):
|
|
super(ParseExpression,self).__init__(savelist)
|
|
if isinstance( exprs, _generatorType ):
|
|
exprs = list(exprs)
|
|
|
|
if isinstance( exprs, basestring ):
|
|
self.exprs = [ ParserElement._literalStringClass( exprs ) ]
|
|
elif isinstance( exprs, Iterable ):
|
|
exprs = list(exprs)
|
|
# if sequence of strings provided, wrap with Literal
|
|
if all(isinstance(expr, basestring) for expr in exprs):
|
|
exprs = map(ParserElement._literalStringClass, exprs)
|
|
self.exprs = list(exprs)
|
|
else:
|
|
try:
|
|
self.exprs = list( exprs )
|
|
except TypeError:
|
|
self.exprs = [ exprs ]
|
|
self.callPreparse = False
|
|
|
|
def __getitem__( self, i ):
|
|
return self.exprs[i]
|
|
|
|
def append( self, other ):
|
|
self.exprs.append( other )
|
|
self.strRepr = None
|
|
return self
|
|
|
|
def leaveWhitespace( self ):
|
|
"""Extends C{leaveWhitespace} defined in base class, and also invokes C{leaveWhitespace} on
|
|
all contained expressions."""
|
|
self.skipWhitespace = False
|
|
self.exprs = [ e.copy() for e in self.exprs ]
|
|
for e in self.exprs:
|
|
e.leaveWhitespace()
|
|
return self
|
|
|
|
def ignore( self, other ):
|
|
if isinstance( other, Suppress ):
|
|
if other not in self.ignoreExprs:
|
|
super( ParseExpression, self).ignore( other )
|
|
for e in self.exprs:
|
|
e.ignore( self.ignoreExprs[-1] )
|
|
else:
|
|
super( ParseExpression, self).ignore( other )
|
|
for e in self.exprs:
|
|
e.ignore( self.ignoreExprs[-1] )
|
|
return self
|
|
|
|
def __str__( self ):
|
|
try:
|
|
return super(ParseExpression,self).__str__()
|
|
except Exception:
|
|
pass
|
|
|
|
if self.strRepr is None:
|
|
self.strRepr = "%s:(%s)" % ( self.__class__.__name__, _ustr(self.exprs) )
|
|
return self.strRepr
|
|
|
|
def streamline( self ):
|
|
super(ParseExpression,self).streamline()
|
|
|
|
for e in self.exprs:
|
|
e.streamline()
|
|
|
|
# collapse nested And's of the form And( And( And( a,b), c), d) to And( a,b,c,d )
|
|
# but only if there are no parse actions or resultsNames on the nested And's
|
|
# (likewise for Or's and MatchFirst's)
|
|
if ( len(self.exprs) == 2 ):
|
|
other = self.exprs[0]
|
|
if ( isinstance( other, self.__class__ ) and
|
|
not(other.parseAction) and
|
|
other.resultsName is None and
|
|
not other.debug ):
|
|
self.exprs = other.exprs[:] + [ self.exprs[1] ]
|
|
self.strRepr = None
|
|
self.mayReturnEmpty |= other.mayReturnEmpty
|
|
self.mayIndexError |= other.mayIndexError
|
|
|
|
other = self.exprs[-1]
|
|
if ( isinstance( other, self.__class__ ) and
|
|
not(other.parseAction) and
|
|
other.resultsName is None and
|
|
not other.debug ):
|
|
self.exprs = self.exprs[:-1] + other.exprs[:]
|
|
self.strRepr = None
|
|
self.mayReturnEmpty |= other.mayReturnEmpty
|
|
self.mayIndexError |= other.mayIndexError
|
|
|
|
self.errmsg = "Expected " + _ustr(self)
|
|
|
|
return self
|
|
|
|
def setResultsName( self, name, listAllMatches=False ):
|
|
ret = super(ParseExpression,self).setResultsName(name,listAllMatches)
|
|
return ret
|
|
|
|
def validate( self, validateTrace=[] ):
|
|
tmp = validateTrace[:]+[self]
|
|
for e in self.exprs:
|
|
e.validate(tmp)
|
|
self.checkRecursion( [] )
|
|
|
|
def copy(self):
|
|
ret = super(ParseExpression,self).copy()
|
|
ret.exprs = [e.copy() for e in self.exprs]
|
|
return ret
|
|
|
|
class And(ParseExpression):
|
|
"""
|
|
Requires all given C{ParseExpression}s to be found in the given order.
|
|
Expressions may be separated by whitespace.
|
|
May be constructed using the C{'+'} operator.
|
|
May also be constructed using the C{'-'} operator, which will suppress backtracking.
|
|
|
|
Example::
|
|
integer = Word(nums)
|
|
name_expr = OneOrMore(Word(alphas))
|
|
|
|
expr = And([integer("id"),name_expr("name"),integer("age")])
|
|
# more easily written as:
|
|
expr = integer("id") + name_expr("name") + integer("age")
|
|
"""
|
|
|
|
class _ErrorStop(Empty):
|
|
def __init__(self, *args, **kwargs):
|
|
super(And._ErrorStop,self).__init__(*args, **kwargs)
|
|
self.name = '-'
|
|
self.leaveWhitespace()
|
|
|
|
def __init__( self, exprs, savelist = True ):
|
|
super(And,self).__init__(exprs, savelist)
|
|
self.mayReturnEmpty = all(e.mayReturnEmpty for e in self.exprs)
|
|
self.setWhitespaceChars( self.exprs[0].whiteChars )
|
|
self.skipWhitespace = self.exprs[0].skipWhitespace
|
|
self.callPreparse = True
|
|
|
|
def parseImpl( self, instring, loc, doActions=True ):
|
|
# pass False as last arg to _parse for first element, since we already
|
|
# pre-parsed the string as part of our And pre-parsing
|
|
loc, resultlist = self.exprs[0]._parse( instring, loc, doActions, callPreParse=False )
|
|
errorStop = False
|
|
for e in self.exprs[1:]:
|
|
if isinstance(e, And._ErrorStop):
|
|
errorStop = True
|
|
continue
|
|
if errorStop:
|
|
try:
|
|
loc, exprtokens = e._parse( instring, loc, doActions )
|
|
except ParseSyntaxException:
|
|
raise
|
|
except ParseBaseException as pe:
|
|
pe.__traceback__ = None
|
|
raise ParseSyntaxException._from_exception(pe)
|
|
except IndexError:
|
|
raise ParseSyntaxException(instring, len(instring), self.errmsg, self)
|
|
else:
|
|
loc, exprtokens = e._parse( instring, loc, doActions )
|
|
if exprtokens or exprtokens.haskeys():
|
|
resultlist += exprtokens
|
|
return loc, resultlist
|
|
|
|
def __iadd__(self, other ):
|
|
if isinstance( other, basestring ):
|
|
other = ParserElement._literalStringClass( other )
|
|
return self.append( other ) #And( [ self, other ] )
|
|
|
|
def checkRecursion( self, parseElementList ):
|
|
subRecCheckList = parseElementList[:] + [ self ]
|
|
for e in self.exprs:
|
|
e.checkRecursion( subRecCheckList )
|
|
if not e.mayReturnEmpty:
|
|
break
|
|
|
|
def __str__( self ):
|
|
if hasattr(self,"name"):
|
|
return self.name
|
|
|
|
if self.strRepr is None:
|
|
self.strRepr = "{" + " ".join(_ustr(e) for e in self.exprs) + "}"
|
|
|
|
return self.strRepr
|
|
|
|
|
|
class Or(ParseExpression):
|
|
"""
|
|
Requires that at least one C{ParseExpression} is found.
|
|
If two expressions match, the expression that matches the longest string will be used.
|
|
May be constructed using the C{'^'} operator.
|
|
|
|
Example::
|
|
# construct Or using '^' operator
|
|
|
|
number = Word(nums) ^ Combine(Word(nums) + '.' + Word(nums))
|
|
print(number.searchString("123 3.1416 789"))
|
|
prints::
|
|
[['123'], ['3.1416'], ['789']]
|
|
"""
|
|
def __init__( self, exprs, savelist = False ):
|
|
super(Or,self).__init__(exprs, savelist)
|
|
if self.exprs:
|
|
self.mayReturnEmpty = any(e.mayReturnEmpty for e in self.exprs)
|
|
else:
|
|
self.mayReturnEmpty = True
|
|
|
|
def parseImpl( self, instring, loc, doActions=True ):
|
|
maxExcLoc = -1
|
|
maxException = None
|
|
matches = []
|
|
for e in self.exprs:
|
|
try:
|
|
loc2 = e.tryParse( instring, loc )
|
|
except ParseException as err:
|
|
err.__traceback__ = None
|
|
if err.loc > maxExcLoc:
|
|
maxException = err
|
|
maxExcLoc = err.loc
|
|
except IndexError:
|
|
if len(instring) > maxExcLoc:
|
|
maxException = ParseException(instring,len(instring),e.errmsg,self)
|
|
maxExcLoc = len(instring)
|
|
else:
|
|
# save match among all matches, to retry longest to shortest
|
|
matches.append((loc2, e))
|
|
|
|
if matches:
|
|
matches.sort(key=lambda x: -x[0])
|
|
for _,e in matches:
|
|
try:
|
|
return e._parse( instring, loc, doActions )
|
|
except ParseException as err:
|
|
err.__traceback__ = None
|
|
if err.loc > maxExcLoc:
|
|
maxException = err
|
|
maxExcLoc = err.loc
|
|
|
|
if maxException is not None:
|
|
maxException.msg = self.errmsg
|
|
raise maxException
|
|
else:
|
|
raise ParseException(instring, loc, "no defined alternatives to match", self)
|
|
|
|
|
|
def __ixor__(self, other ):
|
|
if isinstance( other, basestring ):
|
|
other = ParserElement._literalStringClass( other )
|
|
return self.append( other ) #Or( [ self, other ] )
|
|
|
|
def __str__( self ):
|
|
if hasattr(self,"name"):
|
|
return self.name
|
|
|
|
if self.strRepr is None:
|
|
self.strRepr = "{" + " ^ ".join(_ustr(e) for e in self.exprs) + "}"
|
|
|
|
return self.strRepr
|
|
|
|
def checkRecursion( self, parseElementList ):
|
|
subRecCheckList = parseElementList[:] + [ self ]
|
|
for e in self.exprs:
|
|
e.checkRecursion( subRecCheckList )
|
|
|
|
|
|
class MatchFirst(ParseExpression):
|
|
"""
|
|
Requires that at least one C{ParseExpression} is found.
|
|
If two expressions match, the first one listed is the one that will match.
|
|
May be constructed using the C{'|'} operator.
|
|
|
|
Example::
|
|
# construct MatchFirst using '|' operator
|
|
|
|
# watch the order of expressions to match
|
|
number = Word(nums) | Combine(Word(nums) + '.' + Word(nums))
|
|
print(number.searchString("123 3.1416 789")) # Fail! -> [['123'], ['3'], ['1416'], ['789']]
|
|
|
|
# put more selective expression first
|
|
number = Combine(Word(nums) + '.' + Word(nums)) | Word(nums)
|
|
print(number.searchString("123 3.1416 789")) # Better -> [['123'], ['3.1416'], ['789']]
|
|
"""
|
|
def __init__( self, exprs, savelist = False ):
|
|
super(MatchFirst,self).__init__(exprs, savelist)
|
|
if self.exprs:
|
|
self.mayReturnEmpty = any(e.mayReturnEmpty for e in self.exprs)
|
|
else:
|
|
self.mayReturnEmpty = True
|
|
|
|
def parseImpl( self, instring, loc, doActions=True ):
|
|
maxExcLoc = -1
|
|
maxException = None
|
|
for e in self.exprs:
|
|
try:
|
|
ret = e._parse( instring, loc, doActions )
|
|
return ret
|
|
except ParseException as err:
|
|
if err.loc > maxExcLoc:
|
|
maxException = err
|
|
maxExcLoc = err.loc
|
|
except IndexError:
|
|
if len(instring) > maxExcLoc:
|
|
maxException = ParseException(instring,len(instring),e.errmsg,self)
|
|
maxExcLoc = len(instring)
|
|
|
|
# only got here if no expression matched, raise exception for match that made it the furthest
|
|
else:
|
|
if maxException is not None:
|
|
maxException.msg = self.errmsg
|
|
raise maxException
|
|
else:
|
|
raise ParseException(instring, loc, "no defined alternatives to match", self)
|
|
|
|
def __ior__(self, other ):
|
|
if isinstance( other, basestring ):
|
|
other = ParserElement._literalStringClass( other )
|
|
return self.append( other ) #MatchFirst( [ self, other ] )
|
|
|
|
def __str__( self ):
|
|
if hasattr(self,"name"):
|
|
return self.name
|
|
|
|
if self.strRepr is None:
|
|
self.strRepr = "{" + " | ".join(_ustr(e) for e in self.exprs) + "}"
|
|
|
|
return self.strRepr
|
|
|
|
def checkRecursion( self, parseElementList ):
|
|
subRecCheckList = parseElementList[:] + [ self ]
|
|
for e in self.exprs:
|
|
e.checkRecursion( subRecCheckList )
|
|
|
|
|
|
class Each(ParseExpression):
|
|
"""
|
|
Requires all given C{ParseExpression}s to be found, but in any order.
|
|
Expressions may be separated by whitespace.
|
|
May be constructed using the C{'&'} operator.
|
|
|
|
Example::
|
|
color = oneOf("RED ORANGE YELLOW GREEN BLUE PURPLE BLACK WHITE BROWN")
|
|
shape_type = oneOf("SQUARE CIRCLE TRIANGLE STAR HEXAGON OCTAGON")
|
|
integer = Word(nums)
|
|
shape_attr = "shape:" + shape_type("shape")
|
|
posn_attr = "posn:" + Group(integer("x") + ',' + integer("y"))("posn")
|
|
color_attr = "color:" + color("color")
|
|
size_attr = "size:" + integer("size")
|
|
|
|
# use Each (using operator '&') to accept attributes in any order
|
|
# (shape and posn are required, color and size are optional)
|
|
shape_spec = shape_attr & posn_attr & Optional(color_attr) & Optional(size_attr)
|
|
|
|
shape_spec.runTests('''
|
|
shape: SQUARE color: BLACK posn: 100, 120
|
|
shape: CIRCLE size: 50 color: BLUE posn: 50,80
|
|
color:GREEN size:20 shape:TRIANGLE posn:20,40
|
|
'''
|
|
)
|
|
prints::
|
|
shape: SQUARE color: BLACK posn: 100, 120
|
|
['shape:', 'SQUARE', 'color:', 'BLACK', 'posn:', ['100', ',', '120']]
|
|
- color: BLACK
|
|
- posn: ['100', ',', '120']
|
|
- x: 100
|
|
- y: 120
|
|
- shape: SQUARE
|
|
|
|
|
|
shape: CIRCLE size: 50 color: BLUE posn: 50,80
|
|
['shape:', 'CIRCLE', 'size:', '50', 'color:', 'BLUE', 'posn:', ['50', ',', '80']]
|
|
- color: BLUE
|
|
- posn: ['50', ',', '80']
|
|
- x: 50
|
|
- y: 80
|
|
- shape: CIRCLE
|
|
- size: 50
|
|
|
|
|
|
color: GREEN size: 20 shape: TRIANGLE posn: 20,40
|
|
['color:', 'GREEN', 'size:', '20', 'shape:', 'TRIANGLE', 'posn:', ['20', ',', '40']]
|
|
- color: GREEN
|
|
- posn: ['20', ',', '40']
|
|
- x: 20
|
|
- y: 40
|
|
- shape: TRIANGLE
|
|
- size: 20
|
|
"""
|
|
def __init__( self, exprs, savelist = True ):
|
|
super(Each,self).__init__(exprs, savelist)
|
|
self.mayReturnEmpty = all(e.mayReturnEmpty for e in self.exprs)
|
|
self.skipWhitespace = True
|
|
self.initExprGroups = True
|
|
|
|
def parseImpl( self, instring, loc, doActions=True ):
|
|
if self.initExprGroups:
|
|
self.opt1map = dict((id(e.expr),e) for e in self.exprs if isinstance(e,Optional))
|
|
opt1 = [ e.expr for e in self.exprs if isinstance(e,Optional) ]
|
|
opt2 = [ e for e in self.exprs if e.mayReturnEmpty and not isinstance(e,Optional)]
|
|
self.optionals = opt1 + opt2
|
|
self.multioptionals = [ e.expr for e in self.exprs if isinstance(e,ZeroOrMore) ]
|
|
self.multirequired = [ e.expr for e in self.exprs if isinstance(e,OneOrMore) ]
|
|
self.required = [ e for e in self.exprs if not isinstance(e,(Optional,ZeroOrMore,OneOrMore)) ]
|
|
self.required += self.multirequired
|
|
self.initExprGroups = False
|
|
tmpLoc = loc
|
|
tmpReqd = self.required[:]
|
|
tmpOpt = self.optionals[:]
|
|
matchOrder = []
|
|
|
|
keepMatching = True
|
|
while keepMatching:
|
|
tmpExprs = tmpReqd + tmpOpt + self.multioptionals + self.multirequired
|
|
failed = []
|
|
for e in tmpExprs:
|
|
try:
|
|
tmpLoc = e.tryParse( instring, tmpLoc )
|
|
except ParseException:
|
|
failed.append(e)
|
|
else:
|
|
matchOrder.append(self.opt1map.get(id(e),e))
|
|
if e in tmpReqd:
|
|
tmpReqd.remove(e)
|
|
elif e in tmpOpt:
|
|
tmpOpt.remove(e)
|
|
if len(failed) == len(tmpExprs):
|
|
keepMatching = False
|
|
|
|
if tmpReqd:
|
|
missing = ", ".join(_ustr(e) for e in tmpReqd)
|
|
raise ParseException(instring,loc,"Missing one or more required elements (%s)" % missing )
|
|
|
|
# add any unmatched Optionals, in case they have default values defined
|
|
matchOrder += [e for e in self.exprs if isinstance(e,Optional) and e.expr in tmpOpt]
|
|
|
|
resultlist = []
|
|
for e in matchOrder:
|
|
loc,results = e._parse(instring,loc,doActions)
|
|
resultlist.append(results)
|
|
|
|
finalResults = sum(resultlist, ParseResults([]))
|
|
return loc, finalResults
|
|
|
|
def __str__( self ):
|
|
if hasattr(self,"name"):
|
|
return self.name
|
|
|
|
if self.strRepr is None:
|
|
self.strRepr = "{" + " & ".join(_ustr(e) for e in self.exprs) + "}"
|
|
|
|
return self.strRepr
|
|
|
|
def checkRecursion( self, parseElementList ):
|
|
subRecCheckList = parseElementList[:] + [ self ]
|
|
for e in self.exprs:
|
|
e.checkRecursion( subRecCheckList )
|
|
|
|
|
|
class ParseElementEnhance(ParserElement):
|
|
"""
|
|
Abstract subclass of C{ParserElement}, for combining and post-processing parsed tokens.
|
|
"""
|
|
def __init__( self, expr, savelist=False ):
|
|
super(ParseElementEnhance,self).__init__(savelist)
|
|
if isinstance( expr, basestring ):
|
|
if issubclass(ParserElement._literalStringClass, Token):
|
|
expr = ParserElement._literalStringClass(expr)
|
|
else:
|
|
expr = ParserElement._literalStringClass(Literal(expr))
|
|
self.expr = expr
|
|
self.strRepr = None
|
|
if expr is not None:
|
|
self.mayIndexError = expr.mayIndexError
|
|
self.mayReturnEmpty = expr.mayReturnEmpty
|
|
self.setWhitespaceChars( expr.whiteChars )
|
|
self.skipWhitespace = expr.skipWhitespace
|
|
self.saveAsList = expr.saveAsList
|
|
self.callPreparse = expr.callPreparse
|
|
self.ignoreExprs.extend(expr.ignoreExprs)
|
|
|
|
def parseImpl( self, instring, loc, doActions=True ):
|
|
if self.expr is not None:
|
|
return self.expr._parse( instring, loc, doActions, callPreParse=False )
|
|
else:
|
|
raise ParseException("",loc,self.errmsg,self)
|
|
|
|
def leaveWhitespace( self ):
|
|
self.skipWhitespace = False
|
|
self.expr = self.expr.copy()
|
|
if self.expr is not None:
|
|
self.expr.leaveWhitespace()
|
|
return self
|
|
|
|
def ignore( self, other ):
|
|
if isinstance( other, Suppress ):
|
|
if other not in self.ignoreExprs:
|
|
super( ParseElementEnhance, self).ignore( other )
|
|
if self.expr is not None:
|
|
self.expr.ignore( self.ignoreExprs[-1] )
|
|
else:
|
|
super( ParseElementEnhance, self).ignore( other )
|
|
if self.expr is not None:
|
|
self.expr.ignore( self.ignoreExprs[-1] )
|
|
return self
|
|
|
|
def streamline( self ):
|
|
super(ParseElementEnhance,self).streamline()
|
|
if self.expr is not None:
|
|
self.expr.streamline()
|
|
return self
|
|
|
|
def checkRecursion( self, parseElementList ):
|
|
if self in parseElementList:
|
|
raise RecursiveGrammarException( parseElementList+[self] )
|
|
subRecCheckList = parseElementList[:] + [ self ]
|
|
if self.expr is not None:
|
|
self.expr.checkRecursion( subRecCheckList )
|
|
|
|
def validate( self, validateTrace=[] ):
|
|
tmp = validateTrace[:]+[self]
|
|
if self.expr is not None:
|
|
self.expr.validate(tmp)
|
|
self.checkRecursion( [] )
|
|
|
|
def __str__( self ):
|
|
try:
|
|
return super(ParseElementEnhance,self).__str__()
|
|
except Exception:
|
|
pass
|
|
|
|
if self.strRepr is None and self.expr is not None:
|
|
self.strRepr = "%s:(%s)" % ( self.__class__.__name__, _ustr(self.expr) )
|
|
return self.strRepr
|
|
|
|
|
|
class FollowedBy(ParseElementEnhance):
|
|
"""
|
|
Lookahead matching of the given parse expression. C{FollowedBy}
|
|
does I{not} advance the parsing position within the input string, it only
|
|
verifies that the specified parse expression matches at the current
|
|
position. C{FollowedBy} always returns a null token list.
|
|
|
|
Example::
|
|
# use FollowedBy to match a label only if it is followed by a ':'
|
|
data_word = Word(alphas)
|
|
label = data_word + FollowedBy(':')
|
|
attr_expr = Group(label + Suppress(':') + OneOrMore(data_word, stopOn=label).setParseAction(' '.join))
|
|
|
|
OneOrMore(attr_expr).parseString("shape: SQUARE color: BLACK posn: upper left").pprint()
|
|
prints::
|
|
[['shape', 'SQUARE'], ['color', 'BLACK'], ['posn', 'upper left']]
|
|
"""
|
|
def __init__( self, expr ):
|
|
super(FollowedBy,self).__init__(expr)
|
|
self.mayReturnEmpty = True
|
|
|
|
def parseImpl( self, instring, loc, doActions=True ):
|
|
self.expr.tryParse( instring, loc )
|
|
return loc, []
|
|
|
|
|
|
class NotAny(ParseElementEnhance):
|
|
"""
|
|
Lookahead to disallow matching with the given parse expression. C{NotAny}
|
|
does I{not} advance the parsing position within the input string, it only
|
|
verifies that the specified parse expression does I{not} match at the current
|
|
position. Also, C{NotAny} does I{not} skip over leading whitespace. C{NotAny}
|
|
always returns a null token list. May be constructed using the '~' operator.
|
|
|
|
Example::
|
|
|
|
"""
|
|
def __init__( self, expr ):
|
|
super(NotAny,self).__init__(expr)
|
|
#~ self.leaveWhitespace()
|
|
self.skipWhitespace = False # do NOT use self.leaveWhitespace(), don't want to propagate to exprs
|
|
self.mayReturnEmpty = True
|
|
self.errmsg = "Found unwanted token, "+_ustr(self.expr)
|
|
|
|
def parseImpl( self, instring, loc, doActions=True ):
|
|
if self.expr.canParseNext(instring, loc):
|
|
raise ParseException(instring, loc, self.errmsg, self)
|
|
return loc, []
|
|
|
|
def __str__( self ):
|
|
if hasattr(self,"name"):
|
|
return self.name
|
|
|
|
if self.strRepr is None:
|
|
self.strRepr = "~{" + _ustr(self.expr) + "}"
|
|
|
|
return self.strRepr
|
|
|
|
class _MultipleMatch(ParseElementEnhance):
|
|
def __init__( self, expr, stopOn=None):
|
|
super(_MultipleMatch, self).__init__(expr)
|
|
self.saveAsList = True
|
|
ender = stopOn
|
|
if isinstance(ender, basestring):
|
|
ender = ParserElement._literalStringClass(ender)
|
|
self.not_ender = ~ender if ender is not None else None
|
|
|
|
def parseImpl( self, instring, loc, doActions=True ):
|
|
self_expr_parse = self.expr._parse
|
|
self_skip_ignorables = self._skipIgnorables
|
|
check_ender = self.not_ender is not None
|
|
if check_ender:
|
|
try_not_ender = self.not_ender.tryParse
|
|
|
|
# must be at least one (but first see if we are the stopOn sentinel;
|
|
# if so, fail)
|
|
if check_ender:
|
|
try_not_ender(instring, loc)
|
|
loc, tokens = self_expr_parse( instring, loc, doActions, callPreParse=False )
|
|
try:
|
|
hasIgnoreExprs = (not not self.ignoreExprs)
|
|
while 1:
|
|
if check_ender:
|
|
try_not_ender(instring, loc)
|
|
if hasIgnoreExprs:
|
|
preloc = self_skip_ignorables( instring, loc )
|
|
else:
|
|
preloc = loc
|
|
loc, tmptokens = self_expr_parse( instring, preloc, doActions )
|
|
if tmptokens or tmptokens.haskeys():
|
|
tokens += tmptokens
|
|
except (ParseException,IndexError):
|
|
pass
|
|
|
|
return loc, tokens
|
|
|
|
class OneOrMore(_MultipleMatch):
|
|
"""
|
|
Repetition of one or more of the given expression.
|
|
|
|
Parameters:
|
|
- expr - expression that must match one or more times
|
|
- stopOn - (default=C{None}) - expression for a terminating sentinel
|
|
(only required if the sentinel would ordinarily match the repetition
|
|
expression)
|
|
|
|
Example::
|
|
data_word = Word(alphas)
|
|
label = data_word + FollowedBy(':')
|
|
attr_expr = Group(label + Suppress(':') + OneOrMore(data_word).setParseAction(' '.join))
|
|
|
|
text = "shape: SQUARE posn: upper left color: BLACK"
|
|
OneOrMore(attr_expr).parseString(text).pprint() # Fail! read 'color' as data instead of next label -> [['shape', 'SQUARE color']]
|
|
|
|
# use stopOn attribute for OneOrMore to avoid reading label string as part of the data
|
|
attr_expr = Group(label + Suppress(':') + OneOrMore(data_word, stopOn=label).setParseAction(' '.join))
|
|
OneOrMore(attr_expr).parseString(text).pprint() # Better -> [['shape', 'SQUARE'], ['posn', 'upper left'], ['color', 'BLACK']]
|
|
|
|
# could also be written as
|
|
(attr_expr * (1,)).parseString(text).pprint()
|
|
"""
|
|
|
|
def __str__( self ):
|
|
if hasattr(self,"name"):
|
|
return self.name
|
|
|
|
if self.strRepr is None:
|
|
self.strRepr = "{" + _ustr(self.expr) + "}..."
|
|
|
|
return self.strRepr
|
|
|
|
class ZeroOrMore(_MultipleMatch):
|
|
"""
|
|
Optional repetition of zero or more of the given expression.
|
|
|
|
Parameters:
|
|
- expr - expression that must match zero or more times
|
|
- stopOn - (default=C{None}) - expression for a terminating sentinel
|
|
(only required if the sentinel would ordinarily match the repetition
|
|
expression)
|
|
|
|
Example: similar to L{OneOrMore}
|
|
"""
|
|
def __init__( self, expr, stopOn=None):
|
|
super(ZeroOrMore,self).__init__(expr, stopOn=stopOn)
|
|
self.mayReturnEmpty = True
|
|
|
|
def parseImpl( self, instring, loc, doActions=True ):
|
|
try:
|
|
return super(ZeroOrMore, self).parseImpl(instring, loc, doActions)
|
|
except (ParseException,IndexError):
|
|
return loc, []
|
|
|
|
def __str__( self ):
|
|
if hasattr(self,"name"):
|
|
return self.name
|
|
|
|
if self.strRepr is None:
|
|
self.strRepr = "[" + _ustr(self.expr) + "]..."
|
|
|
|
return self.strRepr
|
|
|
|
class _NullToken(object):
|
|
def __bool__(self):
|
|
return False
|
|
__nonzero__ = __bool__
|
|
def __str__(self):
|
|
return ""
|
|
|
|
_optionalNotMatched = _NullToken()
|
|
class Optional(ParseElementEnhance):
|
|
"""
|
|
Optional matching of the given expression.
|
|
|
|
Parameters:
|
|
- expr - expression that must match zero or more times
|
|
- default (optional) - value to be returned if the optional expression is not found.
|
|
|
|
Example::
|
|
# US postal code can be a 5-digit zip, plus optional 4-digit qualifier
|
|
zip = Combine(Word(nums, exact=5) + Optional('-' + Word(nums, exact=4)))
|
|
zip.runTests('''
|
|
# traditional ZIP code
|
|
12345
|
|
|
|
# ZIP+4 form
|
|
12101-0001
|
|
|
|
# invalid ZIP
|
|
98765-
|
|
''')
|
|
prints::
|
|
# traditional ZIP code
|
|
12345
|
|
['12345']
|
|
|
|
# ZIP+4 form
|
|
12101-0001
|
|
['12101-0001']
|
|
|
|
# invalid ZIP
|
|
98765-
|
|
^
|
|
FAIL: Expected end of text (at char 5), (line:1, col:6)
|
|
"""
|
|
def __init__( self, expr, default=_optionalNotMatched ):
|
|
super(Optional,self).__init__( expr, savelist=False )
|
|
self.saveAsList = self.expr.saveAsList
|
|
self.defaultValue = default
|
|
self.mayReturnEmpty = True
|
|
|
|
def parseImpl( self, instring, loc, doActions=True ):
|
|
try:
|
|
loc, tokens = self.expr._parse( instring, loc, doActions, callPreParse=False )
|
|
except (ParseException,IndexError):
|
|
if self.defaultValue is not _optionalNotMatched:
|
|
if self.expr.resultsName:
|
|
tokens = ParseResults([ self.defaultValue ])
|
|
tokens[self.expr.resultsName] = self.defaultValue
|
|
else:
|
|
tokens = [ self.defaultValue ]
|
|
else:
|
|
tokens = []
|
|
return loc, tokens
|
|
|
|
def __str__( self ):
|
|
if hasattr(self,"name"):
|
|
return self.name
|
|
|
|
if self.strRepr is None:
|
|
self.strRepr = "[" + _ustr(self.expr) + "]"
|
|
|
|
return self.strRepr
|
|
|
|
class SkipTo(ParseElementEnhance):
|
|
"""
|
|
Token for skipping over all undefined text until the matched expression is found.
|
|
|
|
Parameters:
|
|
- expr - target expression marking the end of the data to be skipped
|
|
- include - (default=C{False}) if True, the target expression is also parsed
|
|
(the skipped text and target expression are returned as a 2-element list).
|
|
- ignore - (default=C{None}) used to define grammars (typically quoted strings and
|
|
comments) that might contain false matches to the target expression
|
|
- failOn - (default=C{None}) define expressions that are not allowed to be
|
|
included in the skipped test; if found before the target expression is found,
|
|
the SkipTo is not a match
|
|
|
|
Example::
|
|
report = '''
|
|
Outstanding Issues Report - 1 Jan 2000
|
|
|
|
# | Severity | Description | Days Open
|
|
-----+----------+-------------------------------------------+-----------
|
|
101 | Critical | Intermittent system crash | 6
|
|
94 | Cosmetic | Spelling error on Login ('log|n') | 14
|
|
79 | Minor | System slow when running too many reports | 47
|
|
'''
|
|
integer = Word(nums)
|
|
SEP = Suppress('|')
|
|
# use SkipTo to simply match everything up until the next SEP
|
|
# - ignore quoted strings, so that a '|' character inside a quoted string does not match
|
|
# - parse action will call token.strip() for each matched token, i.e., the description body
|
|
string_data = SkipTo(SEP, ignore=quotedString)
|
|
string_data.setParseAction(tokenMap(str.strip))
|
|
ticket_expr = (integer("issue_num") + SEP
|
|
+ string_data("sev") + SEP
|
|
+ string_data("desc") + SEP
|
|
+ integer("days_open"))
|
|
|
|
for tkt in ticket_expr.searchString(report):
|
|
print tkt.dump()
|
|
prints::
|
|
['101', 'Critical', 'Intermittent system crash', '6']
|
|
- days_open: 6
|
|
- desc: Intermittent system crash
|
|
- issue_num: 101
|
|
- sev: Critical
|
|
['94', 'Cosmetic', "Spelling error on Login ('log|n')", '14']
|
|
- days_open: 14
|
|
- desc: Spelling error on Login ('log|n')
|
|
- issue_num: 94
|
|
- sev: Cosmetic
|
|
['79', 'Minor', 'System slow when running too many reports', '47']
|
|
- days_open: 47
|
|
- desc: System slow when running too many reports
|
|
- issue_num: 79
|
|
- sev: Minor
|
|
"""
|
|
def __init__( self, other, include=False, ignore=None, failOn=None ):
|
|
super( SkipTo, self ).__init__( other )
|
|
self.ignoreExpr = ignore
|
|
self.mayReturnEmpty = True
|
|
self.mayIndexError = False
|
|
self.includeMatch = include
|
|
self.asList = False
|
|
if isinstance(failOn, basestring):
|
|
self.failOn = ParserElement._literalStringClass(failOn)
|
|
else:
|
|
self.failOn = failOn
|
|
self.errmsg = "No match found for "+_ustr(self.expr)
|
|
|
|
def parseImpl( self, instring, loc, doActions=True ):
|
|
startloc = loc
|
|
instrlen = len(instring)
|
|
expr = self.expr
|
|
expr_parse = self.expr._parse
|
|
self_failOn_canParseNext = self.failOn.canParseNext if self.failOn is not None else None
|
|
self_ignoreExpr_tryParse = self.ignoreExpr.tryParse if self.ignoreExpr is not None else None
|
|
|
|
tmploc = loc
|
|
while tmploc <= instrlen:
|
|
if self_failOn_canParseNext is not None:
|
|
# break if failOn expression matches
|
|
if self_failOn_canParseNext(instring, tmploc):
|
|
break
|
|
|
|
if self_ignoreExpr_tryParse is not None:
|
|
# advance past ignore expressions
|
|
while 1:
|
|
try:
|
|
tmploc = self_ignoreExpr_tryParse(instring, tmploc)
|
|
except ParseBaseException:
|
|
break
|
|
|
|
try:
|
|
expr_parse(instring, tmploc, doActions=False, callPreParse=False)
|
|
except (ParseException, IndexError):
|
|
# no match, advance loc in string
|
|
tmploc += 1
|
|
else:
|
|
# matched skipto expr, done
|
|
break
|
|
|
|
else:
|
|
# ran off the end of the input string without matching skipto expr, fail
|
|
raise ParseException(instring, loc, self.errmsg, self)
|
|
|
|
# build up return values
|
|
loc = tmploc
|
|
skiptext = instring[startloc:loc]
|
|
skipresult = ParseResults(skiptext)
|
|
|
|
if self.includeMatch:
|
|
loc, mat = expr_parse(instring,loc,doActions,callPreParse=False)
|
|
skipresult += mat
|
|
|
|
return loc, skipresult
|
|
|
|
class Forward(ParseElementEnhance):
|
|
"""
|
|
Forward declaration of an expression to be defined later -
|
|
used for recursive grammars, such as algebraic infix notation.
|
|
When the expression is known, it is assigned to the C{Forward} variable using the '<<' operator.
|
|
|
|
Note: take care when assigning to C{Forward} not to overlook precedence of operators.
|
|
Specifically, '|' has a lower precedence than '<<', so that::
|
|
fwdExpr << a | b | c
|
|
will actually be evaluated as::
|
|
(fwdExpr << a) | b | c
|
|
thereby leaving b and c out as parseable alternatives. It is recommended that you
|
|
explicitly group the values inserted into the C{Forward}::
|
|
fwdExpr << (a | b | c)
|
|
Converting to use the '<<=' operator instead will avoid this problem.
|
|
|
|
See L{ParseResults.pprint} for an example of a recursive parser created using
|
|
C{Forward}.
|
|
"""
|
|
def __init__( self, other=None ):
|
|
super(Forward,self).__init__( other, savelist=False )
|
|
|
|
def __lshift__( self, other ):
|
|
if isinstance( other, basestring ):
|
|
other = ParserElement._literalStringClass(other)
|
|
self.expr = other
|
|
self.strRepr = None
|
|
self.mayIndexError = self.expr.mayIndexError
|
|
self.mayReturnEmpty = self.expr.mayReturnEmpty
|
|
self.setWhitespaceChars( self.expr.whiteChars )
|
|
self.skipWhitespace = self.expr.skipWhitespace
|
|
self.saveAsList = self.expr.saveAsList
|
|
self.ignoreExprs.extend(self.expr.ignoreExprs)
|
|
return self
|
|
|
|
def __ilshift__(self, other):
|
|
return self << other
|
|
|
|
def leaveWhitespace( self ):
|
|
self.skipWhitespace = False
|
|
return self
|
|
|
|
def streamline( self ):
|
|
if not self.streamlined:
|
|
self.streamlined = True
|
|
if self.expr is not None:
|
|
self.expr.streamline()
|
|
return self
|
|
|
|
def validate( self, validateTrace=[] ):
|
|
if self not in validateTrace:
|
|
tmp = validateTrace[:]+[self]
|
|
if self.expr is not None:
|
|
self.expr.validate(tmp)
|
|
self.checkRecursion([])
|
|
|
|
def __str__( self ):
|
|
if hasattr(self,"name"):
|
|
return self.name
|
|
return self.__class__.__name__ + ": ..."
|
|
|
|
# stubbed out for now - creates awful memory and perf issues
|
|
self._revertClass = self.__class__
|
|
self.__class__ = _ForwardNoRecurse
|
|
try:
|
|
if self.expr is not None:
|
|
retString = _ustr(self.expr)
|
|
else:
|
|
retString = "None"
|
|
finally:
|
|
self.__class__ = self._revertClass
|
|
return self.__class__.__name__ + ": " + retString
|
|
|
|
def copy(self):
|
|
if self.expr is not None:
|
|
return super(Forward,self).copy()
|
|
else:
|
|
ret = Forward()
|
|
ret <<= self
|
|
return ret
|
|
|
|
class _ForwardNoRecurse(Forward):
|
|
def __str__( self ):
|
|
return "..."
|
|
|
|
class TokenConverter(ParseElementEnhance):
|
|
"""
|
|
Abstract subclass of C{ParseExpression}, for converting parsed results.
|
|
"""
|
|
def __init__( self, expr, savelist=False ):
|
|
super(TokenConverter,self).__init__( expr )#, savelist )
|
|
self.saveAsList = False
|
|
|
|
class Combine(TokenConverter):
|
|
"""
|
|
Converter to concatenate all matching tokens to a single string.
|
|
By default, the matching patterns must also be contiguous in the input string;
|
|
this can be disabled by specifying C{'adjacent=False'} in the constructor.
|
|
|
|
Example::
|
|
real = Word(nums) + '.' + Word(nums)
|
|
print(real.parseString('3.1416')) # -> ['3', '.', '1416']
|
|
# will also erroneously match the following
|
|
print(real.parseString('3. 1416')) # -> ['3', '.', '1416']
|
|
|
|
real = Combine(Word(nums) + '.' + Word(nums))
|
|
print(real.parseString('3.1416')) # -> ['3.1416']
|
|
# no match when there are internal spaces
|
|
print(real.parseString('3. 1416')) # -> Exception: Expected W:(0123...)
|
|
"""
|
|
def __init__( self, expr, joinString="", adjacent=True ):
|
|
super(Combine,self).__init__( expr )
|
|
# suppress whitespace-stripping in contained parse expressions, but re-enable it on the Combine itself
|
|
if adjacent:
|
|
self.leaveWhitespace()
|
|
self.adjacent = adjacent
|
|
self.skipWhitespace = True
|
|
self.joinString = joinString
|
|
self.callPreparse = True
|
|
|
|
def ignore( self, other ):
|
|
if self.adjacent:
|
|
ParserElement.ignore(self, other)
|
|
else:
|
|
super( Combine, self).ignore( other )
|
|
return self
|
|
|
|
def postParse( self, instring, loc, tokenlist ):
|
|
retToks = tokenlist.copy()
|
|
del retToks[:]
|
|
retToks += ParseResults([ "".join(tokenlist._asStringList(self.joinString)) ], modal=self.modalResults)
|
|
|
|
if self.resultsName and retToks.haskeys():
|
|
return [ retToks ]
|
|
else:
|
|
return retToks
|
|
|
|
class Group(TokenConverter):
|
|
"""
|
|
Converter to return the matched tokens as a list - useful for returning tokens of C{L{ZeroOrMore}} and C{L{OneOrMore}} expressions.
|
|
|
|
Example::
|
|
ident = Word(alphas)
|
|
num = Word(nums)
|
|
term = ident | num
|
|
func = ident + Optional(delimitedList(term))
|
|
print(func.parseString("fn a,b,100")) # -> ['fn', 'a', 'b', '100']
|
|
|
|
func = ident + Group(Optional(delimitedList(term)))
|
|
print(func.parseString("fn a,b,100")) # -> ['fn', ['a', 'b', '100']]
|
|
"""
|
|
def __init__( self, expr ):
|
|
super(Group,self).__init__( expr )
|
|
self.saveAsList = True
|
|
|
|
def postParse( self, instring, loc, tokenlist ):
|
|
return [ tokenlist ]
|
|
|
|
class Dict(TokenConverter):
|
|
"""
|
|
Converter to return a repetitive expression as a list, but also as a dictionary.
|
|
Each element can also be referenced using the first token in the expression as its key.
|
|
Useful for tabular report scraping when the first column can be used as a item key.
|
|
|
|
Example::
|
|
data_word = Word(alphas)
|
|
label = data_word + FollowedBy(':')
|
|
attr_expr = Group(label + Suppress(':') + OneOrMore(data_word).setParseAction(' '.join))
|
|
|
|
text = "shape: SQUARE posn: upper left color: light blue texture: burlap"
|
|
attr_expr = (label + Suppress(':') + OneOrMore(data_word, stopOn=label).setParseAction(' '.join))
|
|
|
|
# print attributes as plain groups
|
|
print(OneOrMore(attr_expr).parseString(text).dump())
|
|
|
|
# instead of OneOrMore(expr), parse using Dict(OneOrMore(Group(expr))) - Dict will auto-assign names
|
|
result = Dict(OneOrMore(Group(attr_expr))).parseString(text)
|
|
print(result.dump())
|
|
|
|
# access named fields as dict entries, or output as dict
|
|
print(result['shape'])
|
|
print(result.asDict())
|
|
prints::
|
|
['shape', 'SQUARE', 'posn', 'upper left', 'color', 'light blue', 'texture', 'burlap']
|
|
|
|
[['shape', 'SQUARE'], ['posn', 'upper left'], ['color', 'light blue'], ['texture', 'burlap']]
|
|
- color: light blue
|
|
- posn: upper left
|
|
- shape: SQUARE
|
|
- texture: burlap
|
|
SQUARE
|
|
{'color': 'light blue', 'posn': 'upper left', 'texture': 'burlap', 'shape': 'SQUARE'}
|
|
See more examples at L{ParseResults} of accessing fields by results name.
|
|
"""
|
|
def __init__( self, expr ):
|
|
super(Dict,self).__init__( expr )
|
|
self.saveAsList = True
|
|
|
|
def postParse( self, instring, loc, tokenlist ):
|
|
for i,tok in enumerate(tokenlist):
|
|
if len(tok) == 0:
|
|
continue
|
|
ikey = tok[0]
|
|
if isinstance(ikey,int):
|
|
ikey = _ustr(tok[0]).strip()
|
|
if len(tok)==1:
|
|
tokenlist[ikey] = _ParseResultsWithOffset("",i)
|
|
elif len(tok)==2 and not isinstance(tok[1],ParseResults):
|
|
tokenlist[ikey] = _ParseResultsWithOffset(tok[1],i)
|
|
else:
|
|
dictvalue = tok.copy() #ParseResults(i)
|
|
del dictvalue[0]
|
|
if len(dictvalue)!= 1 or (isinstance(dictvalue,ParseResults) and dictvalue.haskeys()):
|
|
tokenlist[ikey] = _ParseResultsWithOffset(dictvalue,i)
|
|
else:
|
|
tokenlist[ikey] = _ParseResultsWithOffset(dictvalue[0],i)
|
|
|
|
if self.resultsName:
|
|
return [ tokenlist ]
|
|
else:
|
|
return tokenlist
|
|
|
|
|
|
class Suppress(TokenConverter):
|
|
"""
|
|
Converter for ignoring the results of a parsed expression.
|
|
|
|
Example::
|
|
source = "a, b, c,d"
|
|
wd = Word(alphas)
|
|
wd_list1 = wd + ZeroOrMore(',' + wd)
|
|
print(wd_list1.parseString(source))
|
|
|
|
# often, delimiters that are useful during parsing are just in the
|
|
# way afterward - use Suppress to keep them out of the parsed output
|
|
wd_list2 = wd + ZeroOrMore(Suppress(',') + wd)
|
|
print(wd_list2.parseString(source))
|
|
prints::
|
|
['a', ',', 'b', ',', 'c', ',', 'd']
|
|
['a', 'b', 'c', 'd']
|
|
(See also L{delimitedList}.)
|
|
"""
|
|
def postParse( self, instring, loc, tokenlist ):
|
|
return []
|
|
|
|
def suppress( self ):
|
|
return self
|
|
|
|
|
|
class OnlyOnce(object):
|
|
"""
|
|
Wrapper for parse actions, to ensure they are only called once.
|
|
"""
|
|
def __init__(self, methodCall):
|
|
self.callable = _trim_arity(methodCall)
|
|
self.called = False
|
|
def __call__(self,s,l,t):
|
|
if not self.called:
|
|
results = self.callable(s,l,t)
|
|
self.called = True
|
|
return results
|
|
raise ParseException(s,l,"")
|
|
def reset(self):
|
|
self.called = False
|
|
|
|
def traceParseAction(f):
|
|
"""
|
|
Decorator for debugging parse actions.
|
|
|
|
When the parse action is called, this decorator will print C{">> entering I{method-name}(line:I{current_source_line}, I{parse_location}, I{matched_tokens})".}
|
|
When the parse action completes, the decorator will print C{"<<"} followed by the returned value, or any exception that the parse action raised.
|
|
|
|
Example::
|
|
wd = Word(alphas)
|
|
|
|
@traceParseAction
|
|
def remove_duplicate_chars(tokens):
|
|
return ''.join(sorted(set(''.join(tokens))))
|
|
|
|
wds = OneOrMore(wd).setParseAction(remove_duplicate_chars)
|
|
print(wds.parseString("slkdjs sld sldd sdlf sdljf"))
|
|
prints::
|
|
>>entering remove_duplicate_chars(line: 'slkdjs sld sldd sdlf sdljf', 0, (['slkdjs', 'sld', 'sldd', 'sdlf', 'sdljf'], {}))
|
|
<<leaving remove_duplicate_chars (ret: 'dfjkls')
|
|
['dfjkls']
|
|
"""
|
|
f = _trim_arity(f)
|
|
def z(*paArgs):
|
|
thisFunc = f.__name__
|
|
s,l,t = paArgs[-3:]
|
|
if len(paArgs)>3:
|
|
thisFunc = paArgs[0].__class__.__name__ + '.' + thisFunc
|
|
sys.stderr.write( ">>entering %s(line: '%s', %d, %r)\n" % (thisFunc,line(l,s),l,t) )
|
|
try:
|
|
ret = f(*paArgs)
|
|
except Exception as exc:
|
|
sys.stderr.write( "<<leaving %s (exception: %s)\n" % (thisFunc,exc) )
|
|
raise
|
|
sys.stderr.write( "<<leaving %s (ret: %r)\n" % (thisFunc,ret) )
|
|
return ret
|
|
try:
|
|
z.__name__ = f.__name__
|
|
except AttributeError:
|
|
pass
|
|
return z
|
|
|
|
#
|
|
# global helpers
|
|
#
|
|
def delimitedList( expr, delim=",", combine=False ):
|
|
"""
|
|
Helper to define a delimited list of expressions - the delimiter defaults to ','.
|
|
By default, the list elements and delimiters can have intervening whitespace, and
|
|
comments, but this can be overridden by passing C{combine=True} in the constructor.
|
|
If C{combine} is set to C{True}, the matching tokens are returned as a single token
|
|
string, with the delimiters included; otherwise, the matching tokens are returned
|
|
as a list of tokens, with the delimiters suppressed.
|
|
|
|
Example::
|
|
delimitedList(Word(alphas)).parseString("aa,bb,cc") # -> ['aa', 'bb', 'cc']
|
|
delimitedList(Word(hexnums), delim=':', combine=True).parseString("AA:BB:CC:DD:EE") # -> ['AA:BB:CC:DD:EE']
|
|
"""
|
|
dlName = _ustr(expr)+" ["+_ustr(delim)+" "+_ustr(expr)+"]..."
|
|
if combine:
|
|
return Combine( expr + ZeroOrMore( delim + expr ) ).setName(dlName)
|
|
else:
|
|
return ( expr + ZeroOrMore( Suppress( delim ) + expr ) ).setName(dlName)
|
|
|
|
def countedArray( expr, intExpr=None ):
|
|
"""
|
|
Helper to define a counted list of expressions.
|
|
This helper defines a pattern of the form::
|
|
integer expr expr expr...
|
|
where the leading integer tells how many expr expressions follow.
|
|
The matched tokens returns the array of expr tokens as a list - the leading count token is suppressed.
|
|
|
|
If C{intExpr} is specified, it should be a pyparsing expression that produces an integer value.
|
|
|
|
Example::
|
|
countedArray(Word(alphas)).parseString('2 ab cd ef') # -> ['ab', 'cd']
|
|
|
|
# in this parser, the leading integer value is given in binary,
|
|
# '10' indicating that 2 values are in the array
|
|
binaryConstant = Word('01').setParseAction(lambda t: int(t[0], 2))
|
|
countedArray(Word(alphas), intExpr=binaryConstant).parseString('10 ab cd ef') # -> ['ab', 'cd']
|
|
"""
|
|
arrayExpr = Forward()
|
|
def countFieldParseAction(s,l,t):
|
|
n = t[0]
|
|
arrayExpr << (n and Group(And([expr]*n)) or Group(empty))
|
|
return []
|
|
if intExpr is None:
|
|
intExpr = Word(nums).setParseAction(lambda t:int(t[0]))
|
|
else:
|
|
intExpr = intExpr.copy()
|
|
intExpr.setName("arrayLen")
|
|
intExpr.addParseAction(countFieldParseAction, callDuringTry=True)
|
|
return ( intExpr + arrayExpr ).setName('(len) ' + _ustr(expr) + '...')
|
|
|
|
def _flatten(L):
|
|
ret = []
|
|
for i in L:
|
|
if isinstance(i,list):
|
|
ret.extend(_flatten(i))
|
|
else:
|
|
ret.append(i)
|
|
return ret
|
|
|
|
def matchPreviousLiteral(expr):
|
|
"""
|
|
Helper to define an expression that is indirectly defined from
|
|
the tokens matched in a previous expression, that is, it looks
|
|
for a 'repeat' of a previous expression. For example::
|
|
first = Word(nums)
|
|
second = matchPreviousLiteral(first)
|
|
matchExpr = first + ":" + second
|
|
will match C{"1:1"}, but not C{"1:2"}. Because this matches a
|
|
previous literal, will also match the leading C{"1:1"} in C{"1:10"}.
|
|
If this is not desired, use C{matchPreviousExpr}.
|
|
Do I{not} use with packrat parsing enabled.
|
|
"""
|
|
rep = Forward()
|
|
def copyTokenToRepeater(s,l,t):
|
|
if t:
|
|
if len(t) == 1:
|
|
rep << t[0]
|
|
else:
|
|
# flatten t tokens
|
|
tflat = _flatten(t.asList())
|
|
rep << And(Literal(tt) for tt in tflat)
|
|
else:
|
|
rep << Empty()
|
|
expr.addParseAction(copyTokenToRepeater, callDuringTry=True)
|
|
rep.setName('(prev) ' + _ustr(expr))
|
|
return rep
|
|
|
|
def matchPreviousExpr(expr):
|
|
"""
|
|
Helper to define an expression that is indirectly defined from
|
|
the tokens matched in a previous expression, that is, it looks
|
|
for a 'repeat' of a previous expression. For example::
|
|
first = Word(nums)
|
|
second = matchPreviousExpr(first)
|
|
matchExpr = first + ":" + second
|
|
will match C{"1:1"}, but not C{"1:2"}. Because this matches by
|
|
expressions, will I{not} match the leading C{"1:1"} in C{"1:10"};
|
|
the expressions are evaluated first, and then compared, so
|
|
C{"1"} is compared with C{"10"}.
|
|
Do I{not} use with packrat parsing enabled.
|
|
"""
|
|
rep = Forward()
|
|
e2 = expr.copy()
|
|
rep <<= e2
|
|
def copyTokenToRepeater(s,l,t):
|
|
matchTokens = _flatten(t.asList())
|
|
def mustMatchTheseTokens(s,l,t):
|
|
theseTokens = _flatten(t.asList())
|
|
if theseTokens != matchTokens:
|
|
raise ParseException("",0,"")
|
|
rep.setParseAction( mustMatchTheseTokens, callDuringTry=True )
|
|
expr.addParseAction(copyTokenToRepeater, callDuringTry=True)
|
|
rep.setName('(prev) ' + _ustr(expr))
|
|
return rep
|
|
|
|
def _escapeRegexRangeChars(s):
|
|
#~ escape these chars: ^-]
|
|
for c in r"\^-]":
|
|
s = s.replace(c,_bslash+c)
|
|
s = s.replace("\n",r"\n")
|
|
s = s.replace("\t",r"\t")
|
|
return _ustr(s)
|
|
|
|
def oneOf( strs, caseless=False, useRegex=True ):
|
|
"""
|
|
Helper to quickly define a set of alternative Literals, and makes sure to do
|
|
longest-first testing when there is a conflict, regardless of the input order,
|
|
but returns a C{L{MatchFirst}} for best performance.
|
|
|
|
Parameters:
|
|
- strs - a string of space-delimited literals, or a collection of string literals
|
|
- caseless - (default=C{False}) - treat all literals as caseless
|
|
- useRegex - (default=C{True}) - as an optimization, will generate a Regex
|
|
object; otherwise, will generate a C{MatchFirst} object (if C{caseless=True}, or
|
|
if creating a C{Regex} raises an exception)
|
|
|
|
Example::
|
|
comp_oper = oneOf("< = > <= >= !=")
|
|
var = Word(alphas)
|
|
number = Word(nums)
|
|
term = var | number
|
|
comparison_expr = term + comp_oper + term
|
|
print(comparison_expr.searchString("B = 12 AA=23 B<=AA AA>12"))
|
|
prints::
|
|
[['B', '=', '12'], ['AA', '=', '23'], ['B', '<=', 'AA'], ['AA', '>', '12']]
|
|
"""
|
|
if caseless:
|
|
isequal = ( lambda a,b: a.upper() == b.upper() )
|
|
masks = ( lambda a,b: b.upper().startswith(a.upper()) )
|
|
parseElementClass = CaselessLiteral
|
|
else:
|
|
isequal = ( lambda a,b: a == b )
|
|
masks = ( lambda a,b: b.startswith(a) )
|
|
parseElementClass = Literal
|
|
|
|
symbols = []
|
|
if isinstance(strs,basestring):
|
|
symbols = strs.split()
|
|
elif isinstance(strs, Iterable):
|
|
symbols = list(strs)
|
|
else:
|
|
warnings.warn("Invalid argument to oneOf, expected string or iterable",
|
|
SyntaxWarning, stacklevel=2)
|
|
if not symbols:
|
|
return NoMatch()
|
|
|
|
i = 0
|
|
while i < len(symbols)-1:
|
|
cur = symbols[i]
|
|
for j,other in enumerate(symbols[i+1:]):
|
|
if ( isequal(other, cur) ):
|
|
del symbols[i+j+1]
|
|
break
|
|
elif ( masks(cur, other) ):
|
|
del symbols[i+j+1]
|
|
symbols.insert(i,other)
|
|
cur = other
|
|
break
|
|
else:
|
|
i += 1
|
|
|
|
if not caseless and useRegex:
|
|
#~ print (strs,"->", "|".join( [ _escapeRegexChars(sym) for sym in symbols] ))
|
|
try:
|
|
if len(symbols)==len("".join(symbols)):
|
|
return Regex( "[%s]" % "".join(_escapeRegexRangeChars(sym) for sym in symbols) ).setName(' | '.join(symbols))
|
|
else:
|
|
return Regex( "|".join(re.escape(sym) for sym in symbols) ).setName(' | '.join(symbols))
|
|
except Exception:
|
|
warnings.warn("Exception creating Regex for oneOf, building MatchFirst",
|
|
SyntaxWarning, stacklevel=2)
|
|
|
|
|
|
# last resort, just use MatchFirst
|
|
return MatchFirst(parseElementClass(sym) for sym in symbols).setName(' | '.join(symbols))
|
|
|
|
def dictOf( key, value ):
|
|
"""
|
|
Helper to easily and clearly define a dictionary by specifying the respective patterns
|
|
for the key and value. Takes care of defining the C{L{Dict}}, C{L{ZeroOrMore}}, and C{L{Group}} tokens
|
|
in the proper order. The key pattern can include delimiting markers or punctuation,
|
|
as long as they are suppressed, thereby leaving the significant key text. The value
|
|
pattern can include named results, so that the C{Dict} results can include named token
|
|
fields.
|
|
|
|
Example::
|
|
text = "shape: SQUARE posn: upper left color: light blue texture: burlap"
|
|
attr_expr = (label + Suppress(':') + OneOrMore(data_word, stopOn=label).setParseAction(' '.join))
|
|
print(OneOrMore(attr_expr).parseString(text).dump())
|
|
|
|
attr_label = label
|
|
attr_value = Suppress(':') + OneOrMore(data_word, stopOn=label).setParseAction(' '.join)
|
|
|
|
# similar to Dict, but simpler call format
|
|
result = dictOf(attr_label, attr_value).parseString(text)
|
|
print(result.dump())
|
|
print(result['shape'])
|
|
print(result.shape) # object attribute access works too
|
|
print(result.asDict())
|
|
prints::
|
|
[['shape', 'SQUARE'], ['posn', 'upper left'], ['color', 'light blue'], ['texture', 'burlap']]
|
|
- color: light blue
|
|
- posn: upper left
|
|
- shape: SQUARE
|
|
- texture: burlap
|
|
SQUARE
|
|
SQUARE
|
|
{'color': 'light blue', 'shape': 'SQUARE', 'posn': 'upper left', 'texture': 'burlap'}
|
|
"""
|
|
return Dict( ZeroOrMore( Group ( key + value ) ) )
|
|
|
|
def originalTextFor(expr, asString=True):
|
|
"""
|
|
Helper to return the original, untokenized text for a given expression. Useful to
|
|
restore the parsed fields of an HTML start tag into the raw tag text itself, or to
|
|
revert separate tokens with intervening whitespace back to the original matching
|
|
input text. By default, returns astring containing the original parsed text.
|
|
|
|
If the optional C{asString} argument is passed as C{False}, then the return value is a
|
|
C{L{ParseResults}} containing any results names that were originally matched, and a
|
|
single token containing the original matched text from the input string. So if
|
|
the expression passed to C{L{originalTextFor}} contains expressions with defined
|
|
results names, you must set C{asString} to C{False} if you want to preserve those
|
|
results name values.
|
|
|
|
Example::
|
|
src = "this is test <b> bold <i>text</i> </b> normal text "
|
|
for tag in ("b","i"):
|
|
opener,closer = makeHTMLTags(tag)
|
|
patt = originalTextFor(opener + SkipTo(closer) + closer)
|
|
print(patt.searchString(src)[0])
|
|
prints::
|
|
['<b> bold <i>text</i> </b>']
|
|
['<i>text</i>']
|
|
"""
|
|
locMarker = Empty().setParseAction(lambda s,loc,t: loc)
|
|
endlocMarker = locMarker.copy()
|
|
endlocMarker.callPreparse = False
|
|
matchExpr = locMarker("_original_start") + expr + endlocMarker("_original_end")
|
|
if asString:
|
|
extractText = lambda s,l,t: s[t._original_start:t._original_end]
|
|
else:
|
|
def extractText(s,l,t):
|
|
t[:] = [s[t.pop('_original_start'):t.pop('_original_end')]]
|
|
matchExpr.setParseAction(extractText)
|
|
matchExpr.ignoreExprs = expr.ignoreExprs
|
|
return matchExpr
|
|
|
|
def ungroup(expr):
|
|
"""
|
|
Helper to undo pyparsing's default grouping of And expressions, even
|
|
if all but one are non-empty.
|
|
"""
|
|
return TokenConverter(expr).setParseAction(lambda t:t[0])
|
|
|
|
def locatedExpr(expr):
|
|
"""
|
|
Helper to decorate a returned token with its starting and ending locations in the input string.
|
|
This helper adds the following results names:
|
|
- locn_start = location where matched expression begins
|
|
- locn_end = location where matched expression ends
|
|
- value = the actual parsed results
|
|
|
|
Be careful if the input text contains C{<TAB>} characters, you may want to call
|
|
C{L{ParserElement.parseWithTabs}}
|
|
|
|
Example::
|
|
wd = Word(alphas)
|
|
for match in locatedExpr(wd).searchString("ljsdf123lksdjjf123lkkjj1222"):
|
|
print(match)
|
|
prints::
|
|
[[0, 'ljsdf', 5]]
|
|
[[8, 'lksdjjf', 15]]
|
|
[[18, 'lkkjj', 23]]
|
|
"""
|
|
locator = Empty().setParseAction(lambda s,l,t: l)
|
|
return Group(locator("locn_start") + expr("value") + locator.copy().leaveWhitespace()("locn_end"))
|
|
|
|
|
|
# convenience constants for positional expressions
|
|
empty = Empty().setName("empty")
|
|
lineStart = LineStart().setName("lineStart")
|
|
lineEnd = LineEnd().setName("lineEnd")
|
|
stringStart = StringStart().setName("stringStart")
|
|
stringEnd = StringEnd().setName("stringEnd")
|
|
|
|
_escapedPunc = Word( _bslash, r"\[]-*.$+^?()~ ", exact=2 ).setParseAction(lambda s,l,t:t[0][1])
|
|
_escapedHexChar = Regex(r"\\0?[xX][0-9a-fA-F]+").setParseAction(lambda s,l,t:unichr(int(t[0].lstrip(r'\0x'),16)))
|
|
_escapedOctChar = Regex(r"\\0[0-7]+").setParseAction(lambda s,l,t:unichr(int(t[0][1:],8)))
|
|
_singleChar = _escapedPunc | _escapedHexChar | _escapedOctChar | CharsNotIn(r'\]', exact=1)
|
|
_charRange = Group(_singleChar + Suppress("-") + _singleChar)
|
|
_reBracketExpr = Literal("[") + Optional("^").setResultsName("negate") + Group( OneOrMore( _charRange | _singleChar ) ).setResultsName("body") + "]"
|
|
|
|
def srange(s):
|
|
r"""
|
|
Helper to easily define string ranges for use in Word construction. Borrows
|
|
syntax from regexp '[]' string range definitions::
|
|
srange("[0-9]") -> "0123456789"
|
|
srange("[a-z]") -> "abcdefghijklmnopqrstuvwxyz"
|
|
srange("[a-z$_]") -> "abcdefghijklmnopqrstuvwxyz$_"
|
|
The input string must be enclosed in []'s, and the returned string is the expanded
|
|
character set joined into a single string.
|
|
The values enclosed in the []'s may be:
|
|
- a single character
|
|
- an escaped character with a leading backslash (such as C{\-} or C{\]})
|
|
- an escaped hex character with a leading C{'\x'} (C{\x21}, which is a C{'!'} character)
|
|
(C{\0x##} is also supported for backwards compatibility)
|
|
- an escaped octal character with a leading C{'\0'} (C{\041}, which is a C{'!'} character)
|
|
- a range of any of the above, separated by a dash (C{'a-z'}, etc.)
|
|
- any combination of the above (C{'aeiouy'}, C{'a-zA-Z0-9_$'}, etc.)
|
|
"""
|
|
_expanded = lambda p: p if not isinstance(p,ParseResults) else ''.join(unichr(c) for c in range(ord(p[0]),ord(p[1])+1))
|
|
try:
|
|
return "".join(_expanded(part) for part in _reBracketExpr.parseString(s).body)
|
|
except Exception:
|
|
return ""
|
|
|
|
def matchOnlyAtCol(n):
|
|
"""
|
|
Helper method for defining parse actions that require matching at a specific
|
|
column in the input text.
|
|
"""
|
|
def verifyCol(strg,locn,toks):
|
|
if col(locn,strg) != n:
|
|
raise ParseException(strg,locn,"matched token not at column %d" % n)
|
|
return verifyCol
|
|
|
|
def replaceWith(replStr):
|
|
"""
|
|
Helper method for common parse actions that simply return a literal value. Especially
|
|
useful when used with C{L{transformString<ParserElement.transformString>}()}.
|
|
|
|
Example::
|
|
num = Word(nums).setParseAction(lambda toks: int(toks[0]))
|
|
na = oneOf("N/A NA").setParseAction(replaceWith(math.nan))
|
|
term = na | num
|
|
|
|
OneOrMore(term).parseString("324 234 N/A 234") # -> [324, 234, nan, 234]
|
|
"""
|
|
return lambda s,l,t: [replStr]
|
|
|
|
def removeQuotes(s,l,t):
|
|
"""
|
|
Helper parse action for removing quotation marks from parsed quoted strings.
|
|
|
|
Example::
|
|
# by default, quotation marks are included in parsed results
|
|
quotedString.parseString("'Now is the Winter of our Discontent'") # -> ["'Now is the Winter of our Discontent'"]
|
|
|
|
# use removeQuotes to strip quotation marks from parsed results
|
|
quotedString.setParseAction(removeQuotes)
|
|
quotedString.parseString("'Now is the Winter of our Discontent'") # -> ["Now is the Winter of our Discontent"]
|
|
"""
|
|
return t[0][1:-1]
|
|
|
|
def tokenMap(func, *args):
|
|
"""
|
|
Helper to define a parse action by mapping a function to all elements of a ParseResults list.If any additional
|
|
args are passed, they are forwarded to the given function as additional arguments after
|
|
the token, as in C{hex_integer = Word(hexnums).setParseAction(tokenMap(int, 16))}, which will convert the
|
|
parsed data to an integer using base 16.
|
|
|
|
Example (compare the last to example in L{ParserElement.transformString}::
|
|
hex_ints = OneOrMore(Word(hexnums)).setParseAction(tokenMap(int, 16))
|
|
hex_ints.runTests('''
|
|
00 11 22 aa FF 0a 0d 1a
|
|
''')
|
|
|
|
upperword = Word(alphas).setParseAction(tokenMap(str.upper))
|
|
OneOrMore(upperword).runTests('''
|
|
my kingdom for a horse
|
|
''')
|
|
|
|
wd = Word(alphas).setParseAction(tokenMap(str.title))
|
|
OneOrMore(wd).setParseAction(' '.join).runTests('''
|
|
now is the winter of our discontent made glorious summer by this sun of york
|
|
''')
|
|
prints::
|
|
00 11 22 aa FF 0a 0d 1a
|
|
[0, 17, 34, 170, 255, 10, 13, 26]
|
|
|
|
my kingdom for a horse
|
|
['MY', 'KINGDOM', 'FOR', 'A', 'HORSE']
|
|
|
|
now is the winter of our discontent made glorious summer by this sun of york
|
|
['Now Is The Winter Of Our Discontent Made Glorious Summer By This Sun Of York']
|
|
"""
|
|
def pa(s,l,t):
|
|
return [func(tokn, *args) for tokn in t]
|
|
|
|
try:
|
|
func_name = getattr(func, '__name__',
|
|
getattr(func, '__class__').__name__)
|
|
except Exception:
|
|
func_name = str(func)
|
|
pa.__name__ = func_name
|
|
|
|
return pa
|
|
|
|
upcaseTokens = tokenMap(lambda t: _ustr(t).upper())
|
|
"""(Deprecated) Helper parse action to convert tokens to upper case. Deprecated in favor of L{pyparsing_common.upcaseTokens}"""
|
|
|
|
downcaseTokens = tokenMap(lambda t: _ustr(t).lower())
|
|
"""(Deprecated) Helper parse action to convert tokens to lower case. Deprecated in favor of L{pyparsing_common.downcaseTokens}"""
|
|
|
|
def _makeTags(tagStr, xml):
|
|
"""Internal helper to construct opening and closing tag expressions, given a tag name"""
|
|
if isinstance(tagStr,basestring):
|
|
resname = tagStr
|
|
tagStr = Keyword(tagStr, caseless=not xml)
|
|
else:
|
|
resname = tagStr.name
|
|
|
|
tagAttrName = Word(alphas,alphanums+"_-:")
|
|
if (xml):
|
|
tagAttrValue = dblQuotedString.copy().setParseAction( removeQuotes )
|
|
openTag = Suppress("<") + tagStr("tag") + \
|
|
Dict(ZeroOrMore(Group( tagAttrName + Suppress("=") + tagAttrValue ))) + \
|
|
Optional("/",default=[False]).setResultsName("empty").setParseAction(lambda s,l,t:t[0]=='/') + Suppress(">")
|
|
else:
|
|
printablesLessRAbrack = "".join(c for c in printables if c not in ">")
|
|
tagAttrValue = quotedString.copy().setParseAction( removeQuotes ) | Word(printablesLessRAbrack)
|
|
openTag = Suppress("<") + tagStr("tag") + \
|
|
Dict(ZeroOrMore(Group( tagAttrName.setParseAction(downcaseTokens) + \
|
|
Optional( Suppress("=") + tagAttrValue ) ))) + \
|
|
Optional("/",default=[False]).setResultsName("empty").setParseAction(lambda s,l,t:t[0]=='/') + Suppress(">")
|
|
closeTag = Combine(_L("</") + tagStr + ">")
|
|
|
|
openTag = openTag.setResultsName("start"+"".join(resname.replace(":"," ").title().split())).setName("<%s>" % resname)
|
|
closeTag = closeTag.setResultsName("end"+"".join(resname.replace(":"," ").title().split())).setName("</%s>" % resname)
|
|
openTag.tag = resname
|
|
closeTag.tag = resname
|
|
return openTag, closeTag
|
|
|
|
def makeHTMLTags(tagStr):
|
|
"""
|
|
Helper to construct opening and closing tag expressions for HTML, given a tag name. Matches
|
|
tags in either upper or lower case, attributes with namespaces and with quoted or unquoted values.
|
|
|
|
Example::
|
|
text = '<td>More info at the <a href="http://pyparsing.wikispaces.com">pyparsing</a> wiki page</td>'
|
|
# makeHTMLTags returns pyparsing expressions for the opening and closing tags as a 2-tuple
|
|
a,a_end = makeHTMLTags("A")
|
|
link_expr = a + SkipTo(a_end)("link_text") + a_end
|
|
|
|
for link in link_expr.searchString(text):
|
|
# attributes in the <A> tag (like "href" shown here) are also accessible as named results
|
|
print(link.link_text, '->', link.href)
|
|
prints::
|
|
pyparsing -> http://pyparsing.wikispaces.com
|
|
"""
|
|
return _makeTags( tagStr, False )
|
|
|
|
def makeXMLTags(tagStr):
|
|
"""
|
|
Helper to construct opening and closing tag expressions for XML, given a tag name. Matches
|
|
tags only in the given upper/lower case.
|
|
|
|
Example: similar to L{makeHTMLTags}
|
|
"""
|
|
return _makeTags( tagStr, True )
|
|
|
|
def withAttribute(*args,**attrDict):
|
|
"""
|
|
Helper to create a validating parse action to be used with start tags created
|
|
with C{L{makeXMLTags}} or C{L{makeHTMLTags}}. Use C{withAttribute} to qualify a starting tag
|
|
with a required attribute value, to avoid false matches on common tags such as
|
|
C{<TD>} or C{<DIV>}.
|
|
|
|
Call C{withAttribute} with a series of attribute names and values. Specify the list
|
|
of filter attributes names and values as:
|
|
- keyword arguments, as in C{(align="right")}, or
|
|
- as an explicit dict with C{**} operator, when an attribute name is also a Python
|
|
reserved word, as in C{**{"class":"Customer", "align":"right"}}
|
|
- a list of name-value tuples, as in ( ("ns1:class", "Customer"), ("ns2:align","right") )
|
|
For attribute names with a namespace prefix, you must use the second form. Attribute
|
|
names are matched insensitive to upper/lower case.
|
|
|
|
If just testing for C{class} (with or without a namespace), use C{L{withClass}}.
|
|
|
|
To verify that the attribute exists, but without specifying a value, pass
|
|
C{withAttribute.ANY_VALUE} as the value.
|
|
|
|
Example::
|
|
html = '''
|
|
<div>
|
|
Some text
|
|
<div type="grid">1 4 0 1 0</div>
|
|
<div type="graph">1,3 2,3 1,1</div>
|
|
<div>this has no type</div>
|
|
</div>
|
|
|
|
'''
|
|
div,div_end = makeHTMLTags("div")
|
|
|
|
# only match div tag having a type attribute with value "grid"
|
|
div_grid = div().setParseAction(withAttribute(type="grid"))
|
|
grid_expr = div_grid + SkipTo(div | div_end)("body")
|
|
for grid_header in grid_expr.searchString(html):
|
|
print(grid_header.body)
|
|
|
|
# construct a match with any div tag having a type attribute, regardless of the value
|
|
div_any_type = div().setParseAction(withAttribute(type=withAttribute.ANY_VALUE))
|
|
div_expr = div_any_type + SkipTo(div | div_end)("body")
|
|
for div_header in div_expr.searchString(html):
|
|
print(div_header.body)
|
|
prints::
|
|
1 4 0 1 0
|
|
|
|
1 4 0 1 0
|
|
1,3 2,3 1,1
|
|
"""
|
|
if args:
|
|
attrs = args[:]
|
|
else:
|
|
attrs = attrDict.items()
|
|
attrs = [(k,v) for k,v in attrs]
|
|
def pa(s,l,tokens):
|
|
for attrName,attrValue in attrs:
|
|
if attrName not in tokens:
|
|
raise ParseException(s,l,"no matching attribute " + attrName)
|
|
if attrValue != withAttribute.ANY_VALUE and tokens[attrName] != attrValue:
|
|
raise ParseException(s,l,"attribute '%s' has value '%s', must be '%s'" %
|
|
(attrName, tokens[attrName], attrValue))
|
|
return pa
|
|
withAttribute.ANY_VALUE = object()
|
|
|
|
def withClass(classname, namespace=''):
|
|
"""
|
|
Simplified version of C{L{withAttribute}} when matching on a div class - made
|
|
difficult because C{class} is a reserved word in Python.
|
|
|
|
Example::
|
|
html = '''
|
|
<div>
|
|
Some text
|
|
<div class="grid">1 4 0 1 0</div>
|
|
<div class="graph">1,3 2,3 1,1</div>
|
|
<div>this <div> has no class</div>
|
|
</div>
|
|
|
|
'''
|
|
div,div_end = makeHTMLTags("div")
|
|
div_grid = div().setParseAction(withClass("grid"))
|
|
|
|
grid_expr = div_grid + SkipTo(div | div_end)("body")
|
|
for grid_header in grid_expr.searchString(html):
|
|
print(grid_header.body)
|
|
|
|
div_any_type = div().setParseAction(withClass(withAttribute.ANY_VALUE))
|
|
div_expr = div_any_type + SkipTo(div | div_end)("body")
|
|
for div_header in div_expr.searchString(html):
|
|
print(div_header.body)
|
|
prints::
|
|
1 4 0 1 0
|
|
|
|
1 4 0 1 0
|
|
1,3 2,3 1,1
|
|
"""
|
|
classattr = "%s:class" % namespace if namespace else "class"
|
|
return withAttribute(**{classattr : classname})
|
|
|
|
opAssoc = _Constants()
|
|
opAssoc.LEFT = object()
|
|
opAssoc.RIGHT = object()
|
|
|
|
def infixNotation( baseExpr, opList, lpar=Suppress('('), rpar=Suppress(')') ):
|
|
"""
|
|
Helper method for constructing grammars of expressions made up of
|
|
operators working in a precedence hierarchy. Operators may be unary or
|
|
binary, left- or right-associative. Parse actions can also be attached
|
|
to operator expressions. The generated parser will also recognize the use
|
|
of parentheses to override operator precedences (see example below).
|
|
|
|
Note: if you define a deep operator list, you may see performance issues
|
|
when using infixNotation. See L{ParserElement.enablePackrat} for a
|
|
mechanism to potentially improve your parser performance.
|
|
|
|
Parameters:
|
|
- baseExpr - expression representing the most basic element for the nested
|
|
- opList - list of tuples, one for each operator precedence level in the
|
|
expression grammar; each tuple is of the form
|
|
(opExpr, numTerms, rightLeftAssoc, parseAction), where:
|
|
- opExpr is the pyparsing expression for the operator;
|
|
may also be a string, which will be converted to a Literal;
|
|
if numTerms is 3, opExpr is a tuple of two expressions, for the
|
|
two operators separating the 3 terms
|
|
- numTerms is the number of terms for this operator (must
|
|
be 1, 2, or 3)
|
|
- rightLeftAssoc is the indicator whether the operator is
|
|
right or left associative, using the pyparsing-defined
|
|
constants C{opAssoc.RIGHT} and C{opAssoc.LEFT}.
|
|
- parseAction is the parse action to be associated with
|
|
expressions matching this operator expression (the
|
|
parse action tuple member may be omitted); if the parse action
|
|
is passed a tuple or list of functions, this is equivalent to
|
|
calling C{setParseAction(*fn)} (L{ParserElement.setParseAction})
|
|
- lpar - expression for matching left-parentheses (default=C{Suppress('(')})
|
|
- rpar - expression for matching right-parentheses (default=C{Suppress(')')})
|
|
|
|
Example::
|
|
# simple example of four-function arithmetic with ints and variable names
|
|
integer = pyparsing_common.signed_integer
|
|
varname = pyparsing_common.identifier
|
|
|
|
arith_expr = infixNotation(integer | varname,
|
|
[
|
|
('-', 1, opAssoc.RIGHT),
|
|
(oneOf('* /'), 2, opAssoc.LEFT),
|
|
(oneOf('+ -'), 2, opAssoc.LEFT),
|
|
])
|
|
|
|
arith_expr.runTests('''
|
|
5+3*6
|
|
(5+3)*6
|
|
-2--11
|
|
''', fullDump=False)
|
|
prints::
|
|
5+3*6
|
|
[[5, '+', [3, '*', 6]]]
|
|
|
|
(5+3)*6
|
|
[[[5, '+', 3], '*', 6]]
|
|
|
|
-2--11
|
|
[[['-', 2], '-', ['-', 11]]]
|
|
"""
|
|
ret = Forward()
|
|
lastExpr = baseExpr | ( lpar + ret + rpar )
|
|
for i,operDef in enumerate(opList):
|
|
opExpr,arity,rightLeftAssoc,pa = (operDef + (None,))[:4]
|
|
termName = "%s term" % opExpr if arity < 3 else "%s%s term" % opExpr
|
|
if arity == 3:
|
|
if opExpr is None or len(opExpr) != 2:
|
|
raise ValueError("if numterms=3, opExpr must be a tuple or list of two expressions")
|
|
opExpr1, opExpr2 = opExpr
|
|
thisExpr = Forward().setName(termName)
|
|
if rightLeftAssoc == opAssoc.LEFT:
|
|
if arity == 1:
|
|
matchExpr = FollowedBy(lastExpr + opExpr) + Group( lastExpr + OneOrMore( opExpr ) )
|
|
elif arity == 2:
|
|
if opExpr is not None:
|
|
matchExpr = FollowedBy(lastExpr + opExpr + lastExpr) + Group( lastExpr + OneOrMore( opExpr + lastExpr ) )
|
|
else:
|
|
matchExpr = FollowedBy(lastExpr+lastExpr) + Group( lastExpr + OneOrMore(lastExpr) )
|
|
elif arity == 3:
|
|
matchExpr = FollowedBy(lastExpr + opExpr1 + lastExpr + opExpr2 + lastExpr) + \
|
|
Group( lastExpr + opExpr1 + lastExpr + opExpr2 + lastExpr )
|
|
else:
|
|
raise ValueError("operator must be unary (1), binary (2), or ternary (3)")
|
|
elif rightLeftAssoc == opAssoc.RIGHT:
|
|
if arity == 1:
|
|
# try to avoid LR with this extra test
|
|
if not isinstance(opExpr, Optional):
|
|
opExpr = Optional(opExpr)
|
|
matchExpr = FollowedBy(opExpr.expr + thisExpr) + Group( opExpr + thisExpr )
|
|
elif arity == 2:
|
|
if opExpr is not None:
|
|
matchExpr = FollowedBy(lastExpr + opExpr + thisExpr) + Group( lastExpr + OneOrMore( opExpr + thisExpr ) )
|
|
else:
|
|
matchExpr = FollowedBy(lastExpr + thisExpr) + Group( lastExpr + OneOrMore( thisExpr ) )
|
|
elif arity == 3:
|
|
matchExpr = FollowedBy(lastExpr + opExpr1 + thisExpr + opExpr2 + thisExpr) + \
|
|
Group( lastExpr + opExpr1 + thisExpr + opExpr2 + thisExpr )
|
|
else:
|
|
raise ValueError("operator must be unary (1), binary (2), or ternary (3)")
|
|
else:
|
|
raise ValueError("operator must indicate right or left associativity")
|
|
if pa:
|
|
if isinstance(pa, (tuple, list)):
|
|
matchExpr.setParseAction(*pa)
|
|
else:
|
|
matchExpr.setParseAction(pa)
|
|
thisExpr <<= ( matchExpr.setName(termName) | lastExpr )
|
|
lastExpr = thisExpr
|
|
ret <<= lastExpr
|
|
return ret
|
|
|
|
operatorPrecedence = infixNotation
|
|
"""(Deprecated) Former name of C{L{infixNotation}}, will be dropped in a future release."""
|
|
|
|
dblQuotedString = Combine(Regex(r'"(?:[^"\n\r\\]|(?:"")|(?:\\(?:[^x]|x[0-9a-fA-F]+)))*')+'"').setName("string enclosed in double quotes")
|
|
sglQuotedString = Combine(Regex(r"'(?:[^'\n\r\\]|(?:'')|(?:\\(?:[^x]|x[0-9a-fA-F]+)))*")+"'").setName("string enclosed in single quotes")
|
|
quotedString = Combine(Regex(r'"(?:[^"\n\r\\]|(?:"")|(?:\\(?:[^x]|x[0-9a-fA-F]+)))*')+'"'|
|
|
Regex(r"'(?:[^'\n\r\\]|(?:'')|(?:\\(?:[^x]|x[0-9a-fA-F]+)))*")+"'").setName("quotedString using single or double quotes")
|
|
unicodeString = Combine(_L('u') + quotedString.copy()).setName("unicode string literal")
|
|
|
|
def nestedExpr(opener="(", closer=")", content=None, ignoreExpr=quotedString.copy()):
|
|
"""
|
|
Helper method for defining nested lists enclosed in opening and closing
|
|
delimiters ("(" and ")" are the default).
|
|
|
|
Parameters:
|
|
- opener - opening character for a nested list (default=C{"("}); can also be a pyparsing expression
|
|
- closer - closing character for a nested list (default=C{")"}); can also be a pyparsing expression
|
|
- content - expression for items within the nested lists (default=C{None})
|
|
- ignoreExpr - expression for ignoring opening and closing delimiters (default=C{quotedString})
|
|
|
|
If an expression is not provided for the content argument, the nested
|
|
expression will capture all whitespace-delimited content between delimiters
|
|
as a list of separate values.
|
|
|
|
Use the C{ignoreExpr} argument to define expressions that may contain
|
|
opening or closing characters that should not be treated as opening
|
|
or closing characters for nesting, such as quotedString or a comment
|
|
expression. Specify multiple expressions using an C{L{Or}} or C{L{MatchFirst}}.
|
|
The default is L{quotedString}, but if no expressions are to be ignored,
|
|
then pass C{None} for this argument.
|
|
|
|
Example::
|
|
data_type = oneOf("void int short long char float double")
|
|
decl_data_type = Combine(data_type + Optional(Word('*')))
|
|
ident = Word(alphas+'_', alphanums+'_')
|
|
number = pyparsing_common.number
|
|
arg = Group(decl_data_type + ident)
|
|
LPAR,RPAR = map(Suppress, "()")
|
|
|
|
code_body = nestedExpr('{', '}', ignoreExpr=(quotedString | cStyleComment))
|
|
|
|
c_function = (decl_data_type("type")
|
|
+ ident("name")
|
|
+ LPAR + Optional(delimitedList(arg), [])("args") + RPAR
|
|
+ code_body("body"))
|
|
c_function.ignore(cStyleComment)
|
|
|
|
source_code = '''
|
|
int is_odd(int x) {
|
|
return (x%2);
|
|
}
|
|
|
|
int dec_to_hex(char hchar) {
|
|
if (hchar >= '0' && hchar <= '9') {
|
|
return (ord(hchar)-ord('0'));
|
|
} else {
|
|
return (10+ord(hchar)-ord('A'));
|
|
}
|
|
}
|
|
'''
|
|
for func in c_function.searchString(source_code):
|
|
print("%(name)s (%(type)s) args: %(args)s" % func)
|
|
|
|
prints::
|
|
is_odd (int) args: [['int', 'x']]
|
|
dec_to_hex (int) args: [['char', 'hchar']]
|
|
"""
|
|
if opener == closer:
|
|
raise ValueError("opening and closing strings cannot be the same")
|
|
if content is None:
|
|
if isinstance(opener,basestring) and isinstance(closer,basestring):
|
|
if len(opener) == 1 and len(closer)==1:
|
|
if ignoreExpr is not None:
|
|
content = (Combine(OneOrMore(~ignoreExpr +
|
|
CharsNotIn(opener+closer+ParserElement.DEFAULT_WHITE_CHARS,exact=1))
|
|
).setParseAction(lambda t:t[0].strip()))
|
|
else:
|
|
content = (empty.copy()+CharsNotIn(opener+closer+ParserElement.DEFAULT_WHITE_CHARS
|
|
).setParseAction(lambda t:t[0].strip()))
|
|
else:
|
|
if ignoreExpr is not None:
|
|
content = (Combine(OneOrMore(~ignoreExpr +
|
|
~Literal(opener) + ~Literal(closer) +
|
|
CharsNotIn(ParserElement.DEFAULT_WHITE_CHARS,exact=1))
|
|
).setParseAction(lambda t:t[0].strip()))
|
|
else:
|
|
content = (Combine(OneOrMore(~Literal(opener) + ~Literal(closer) +
|
|
CharsNotIn(ParserElement.DEFAULT_WHITE_CHARS,exact=1))
|
|
).setParseAction(lambda t:t[0].strip()))
|
|
else:
|
|
raise ValueError("opening and closing arguments must be strings if no content expression is given")
|
|
ret = Forward()
|
|
if ignoreExpr is not None:
|
|
ret <<= Group( Suppress(opener) + ZeroOrMore( ignoreExpr | ret | content ) + Suppress(closer) )
|
|
else:
|
|
ret <<= Group( Suppress(opener) + ZeroOrMore( ret | content ) + Suppress(closer) )
|
|
ret.setName('nested %s%s expression' % (opener,closer))
|
|
return ret
|
|
|
|
def indentedBlock(blockStatementExpr, indentStack, indent=True):
|
|
"""
|
|
Helper method for defining space-delimited indentation blocks, such as
|
|
those used to define block statements in Python source code.
|
|
|
|
Parameters:
|
|
- blockStatementExpr - expression defining syntax of statement that
|
|
is repeated within the indented block
|
|
- indentStack - list created by caller to manage indentation stack
|
|
(multiple statementWithIndentedBlock expressions within a single grammar
|
|
should share a common indentStack)
|
|
- indent - boolean indicating whether block must be indented beyond the
|
|
the current level; set to False for block of left-most statements
|
|
(default=C{True})
|
|
|
|
A valid block must contain at least one C{blockStatement}.
|
|
|
|
Example::
|
|
data = '''
|
|
def A(z):
|
|
A1
|
|
B = 100
|
|
G = A2
|
|
A2
|
|
A3
|
|
B
|
|
def BB(a,b,c):
|
|
BB1
|
|
def BBA():
|
|
bba1
|
|
bba2
|
|
bba3
|
|
C
|
|
D
|
|
def spam(x,y):
|
|
def eggs(z):
|
|
pass
|
|
'''
|
|
|
|
|
|
indentStack = [1]
|
|
stmt = Forward()
|
|
|
|
identifier = Word(alphas, alphanums)
|
|
funcDecl = ("def" + identifier + Group( "(" + Optional( delimitedList(identifier) ) + ")" ) + ":")
|
|
func_body = indentedBlock(stmt, indentStack)
|
|
funcDef = Group( funcDecl + func_body )
|
|
|
|
rvalue = Forward()
|
|
funcCall = Group(identifier + "(" + Optional(delimitedList(rvalue)) + ")")
|
|
rvalue << (funcCall | identifier | Word(nums))
|
|
assignment = Group(identifier + "=" + rvalue)
|
|
stmt << ( funcDef | assignment | identifier )
|
|
|
|
module_body = OneOrMore(stmt)
|
|
|
|
parseTree = module_body.parseString(data)
|
|
parseTree.pprint()
|
|
prints::
|
|
[['def',
|
|
'A',
|
|
['(', 'z', ')'],
|
|
':',
|
|
[['A1'], [['B', '=', '100']], [['G', '=', 'A2']], ['A2'], ['A3']]],
|
|
'B',
|
|
['def',
|
|
'BB',
|
|
['(', 'a', 'b', 'c', ')'],
|
|
':',
|
|
[['BB1'], [['def', 'BBA', ['(', ')'], ':', [['bba1'], ['bba2'], ['bba3']]]]]],
|
|
'C',
|
|
'D',
|
|
['def',
|
|
'spam',
|
|
['(', 'x', 'y', ')'],
|
|
':',
|
|
[[['def', 'eggs', ['(', 'z', ')'], ':', [['pass']]]]]]]
|
|
"""
|
|
def checkPeerIndent(s,l,t):
|
|
if l >= len(s): return
|
|
curCol = col(l,s)
|
|
if curCol != indentStack[-1]:
|
|
if curCol > indentStack[-1]:
|
|
raise ParseFatalException(s,l,"illegal nesting")
|
|
raise ParseException(s,l,"not a peer entry")
|
|
|
|
def checkSubIndent(s,l,t):
|
|
curCol = col(l,s)
|
|
if curCol > indentStack[-1]:
|
|
indentStack.append( curCol )
|
|
else:
|
|
raise ParseException(s,l,"not a subentry")
|
|
|
|
def checkUnindent(s,l,t):
|
|
if l >= len(s): return
|
|
curCol = col(l,s)
|
|
if not(indentStack and curCol < indentStack[-1] and curCol <= indentStack[-2]):
|
|
raise ParseException(s,l,"not an unindent")
|
|
indentStack.pop()
|
|
|
|
NL = OneOrMore(LineEnd().setWhitespaceChars("\t ").suppress())
|
|
INDENT = (Empty() + Empty().setParseAction(checkSubIndent)).setName('INDENT')
|
|
PEER = Empty().setParseAction(checkPeerIndent).setName('')
|
|
UNDENT = Empty().setParseAction(checkUnindent).setName('UNINDENT')
|
|
if indent:
|
|
smExpr = Group( Optional(NL) +
|
|
#~ FollowedBy(blockStatementExpr) +
|
|
INDENT + (OneOrMore( PEER + Group(blockStatementExpr) + Optional(NL) )) + UNDENT)
|
|
else:
|
|
smExpr = Group( Optional(NL) +
|
|
(OneOrMore( PEER + Group(blockStatementExpr) + Optional(NL) )) )
|
|
blockStatementExpr.ignore(_bslash + LineEnd())
|
|
return smExpr.setName('indented block')
|
|
|
|
alphas8bit = srange(r"[\0xc0-\0xd6\0xd8-\0xf6\0xf8-\0xff]")
|
|
punc8bit = srange(r"[\0xa1-\0xbf\0xd7\0xf7]")
|
|
|
|
anyOpenTag,anyCloseTag = makeHTMLTags(Word(alphas,alphanums+"_:").setName('any tag'))
|
|
_htmlEntityMap = dict(zip("gt lt amp nbsp quot apos".split(),'><& "\''))
|
|
commonHTMLEntity = Regex('&(?P<entity>' + '|'.join(_htmlEntityMap.keys()) +");").setName("common HTML entity")
|
|
def replaceHTMLEntity(t):
|
|
"""Helper parser action to replace common HTML entities with their special characters"""
|
|
return _htmlEntityMap.get(t.entity)
|
|
|
|
# it's easy to get these comment structures wrong - they're very common, so may as well make them available
|
|
cStyleComment = Combine(Regex(r"/\*(?:[^*]|\*(?!/))*") + '*/').setName("C style comment")
|
|
"Comment of the form C{/* ... */}"
|
|
|
|
htmlComment = Regex(r"<!--[\s\S]*?-->").setName("HTML comment")
|
|
"Comment of the form C{<!-- ... -->}"
|
|
|
|
restOfLine = Regex(r".*").leaveWhitespace().setName("rest of line")
|
|
dblSlashComment = Regex(r"//(?:\\\n|[^\n])*").setName("// comment")
|
|
"Comment of the form C{// ... (to end of line)}"
|
|
|
|
cppStyleComment = Combine(Regex(r"/\*(?:[^*]|\*(?!/))*") + '*/'| dblSlashComment).setName("C++ style comment")
|
|
"Comment of either form C{L{cStyleComment}} or C{L{dblSlashComment}}"
|
|
|
|
javaStyleComment = cppStyleComment
|
|
"Same as C{L{cppStyleComment}}"
|
|
|
|
pythonStyleComment = Regex(r"#.*").setName("Python style comment")
|
|
"Comment of the form C{# ... (to end of line)}"
|
|
|
|
_commasepitem = Combine(OneOrMore(Word(printables, excludeChars=',') +
|
|
Optional( Word(" \t") +
|
|
~Literal(",") + ~LineEnd() ) ) ).streamline().setName("commaItem")
|
|
commaSeparatedList = delimitedList( Optional( quotedString.copy() | _commasepitem, default="") ).setName("commaSeparatedList")
|
|
"""(Deprecated) Predefined expression of 1 or more printable words or quoted strings, separated by commas.
|
|
This expression is deprecated in favor of L{pyparsing_common.comma_separated_list}."""
|
|
|
|
# some other useful expressions - using lower-case class name since we are really using this as a namespace
|
|
class pyparsing_common:
|
|
"""
|
|
Here are some common low-level expressions that may be useful in jump-starting parser development:
|
|
- numeric forms (L{integers<integer>}, L{reals<real>}, L{scientific notation<sci_real>})
|
|
- common L{programming identifiers<identifier>}
|
|
- network addresses (L{MAC<mac_address>}, L{IPv4<ipv4_address>}, L{IPv6<ipv6_address>})
|
|
- ISO8601 L{dates<iso8601_date>} and L{datetime<iso8601_datetime>}
|
|
- L{UUID<uuid>}
|
|
- L{comma-separated list<comma_separated_list>}
|
|
Parse actions:
|
|
- C{L{convertToInteger}}
|
|
- C{L{convertToFloat}}
|
|
- C{L{convertToDate}}
|
|
- C{L{convertToDatetime}}
|
|
- C{L{stripHTMLTags}}
|
|
- C{L{upcaseTokens}}
|
|
- C{L{downcaseTokens}}
|
|
|
|
Example::
|
|
pyparsing_common.number.runTests('''
|
|
# any int or real number, returned as the appropriate type
|
|
100
|
|
-100
|
|
+100
|
|
3.14159
|
|
6.02e23
|
|
1e-12
|
|
''')
|
|
|
|
pyparsing_common.fnumber.runTests('''
|
|
# any int or real number, returned as float
|
|
100
|
|
-100
|
|
+100
|
|
3.14159
|
|
6.02e23
|
|
1e-12
|
|
''')
|
|
|
|
pyparsing_common.hex_integer.runTests('''
|
|
# hex numbers
|
|
100
|
|
FF
|
|
''')
|
|
|
|
pyparsing_common.fraction.runTests('''
|
|
# fractions
|
|
1/2
|
|
-3/4
|
|
''')
|
|
|
|
pyparsing_common.mixed_integer.runTests('''
|
|
# mixed fractions
|
|
1
|
|
1/2
|
|
-3/4
|
|
1-3/4
|
|
''')
|
|
|
|
import uuid
|
|
pyparsing_common.uuid.setParseAction(tokenMap(uuid.UUID))
|
|
pyparsing_common.uuid.runTests('''
|
|
# uuid
|
|
12345678-1234-5678-1234-567812345678
|
|
''')
|
|
prints::
|
|
# any int or real number, returned as the appropriate type
|
|
100
|
|
[100]
|
|
|
|
-100
|
|
[-100]
|
|
|
|
+100
|
|
[100]
|
|
|
|
3.14159
|
|
[3.14159]
|
|
|
|
6.02e23
|
|
[6.02e+23]
|
|
|
|
1e-12
|
|
[1e-12]
|
|
|
|
# any int or real number, returned as float
|
|
100
|
|
[100.0]
|
|
|
|
-100
|
|
[-100.0]
|
|
|
|
+100
|
|
[100.0]
|
|
|
|
3.14159
|
|
[3.14159]
|
|
|
|
6.02e23
|
|
[6.02e+23]
|
|
|
|
1e-12
|
|
[1e-12]
|
|
|
|
# hex numbers
|
|
100
|
|
[256]
|
|
|
|
FF
|
|
[255]
|
|
|
|
# fractions
|
|
1/2
|
|
[0.5]
|
|
|
|
-3/4
|
|
[-0.75]
|
|
|
|
# mixed fractions
|
|
1
|
|
[1]
|
|
|
|
1/2
|
|
[0.5]
|
|
|
|
-3/4
|
|
[-0.75]
|
|
|
|
1-3/4
|
|
[1.75]
|
|
|
|
# uuid
|
|
12345678-1234-5678-1234-567812345678
|
|
[UUID('12345678-1234-5678-1234-567812345678')]
|
|
"""
|
|
|
|
convertToInteger = tokenMap(int)
|
|
"""
|
|
Parse action for converting parsed integers to Python int
|
|
"""
|
|
|
|
convertToFloat = tokenMap(float)
|
|
"""
|
|
Parse action for converting parsed numbers to Python float
|
|
"""
|
|
|
|
integer = Word(nums).setName("integer").setParseAction(convertToInteger)
|
|
"""expression that parses an unsigned integer, returns an int"""
|
|
|
|
hex_integer = Word(hexnums).setName("hex integer").setParseAction(tokenMap(int,16))
|
|
"""expression that parses a hexadecimal integer, returns an int"""
|
|
|
|
signed_integer = Regex(r'[+-]?\d+').setName("signed integer").setParseAction(convertToInteger)
|
|
"""expression that parses an integer with optional leading sign, returns an int"""
|
|
|
|
fraction = (signed_integer().setParseAction(convertToFloat) + '/' + signed_integer().setParseAction(convertToFloat)).setName("fraction")
|
|
"""fractional expression of an integer divided by an integer, returns a float"""
|
|
fraction.addParseAction(lambda t: t[0]/t[-1])
|
|
|
|
mixed_integer = (fraction | signed_integer + Optional(Optional('-').suppress() + fraction)).setName("fraction or mixed integer-fraction")
|
|
"""mixed integer of the form 'integer - fraction', with optional leading integer, returns float"""
|
|
mixed_integer.addParseAction(sum)
|
|
|
|
real = Regex(r'[+-]?\d+\.\d*').setName("real number").setParseAction(convertToFloat)
|
|
"""expression that parses a floating point number and returns a float"""
|
|
|
|
sci_real = Regex(r'[+-]?\d+([eE][+-]?\d+|\.\d*([eE][+-]?\d+)?)').setName("real number with scientific notation").setParseAction(convertToFloat)
|
|
"""expression that parses a floating point number with optional scientific notation and returns a float"""
|
|
|
|
# streamlining this expression makes the docs nicer-looking
|
|
number = (sci_real | real | signed_integer).streamline()
|
|
"""any numeric expression, returns the corresponding Python type"""
|
|
|
|
fnumber = Regex(r'[+-]?\d+\.?\d*([eE][+-]?\d+)?').setName("fnumber").setParseAction(convertToFloat)
|
|
"""any int or real number, returned as float"""
|
|
|
|
identifier = Word(alphas+'_', alphanums+'_').setName("identifier")
|
|
"""typical code identifier (leading alpha or '_', followed by 0 or more alphas, nums, or '_')"""
|
|
|
|
ipv4_address = Regex(r'(25[0-5]|2[0-4][0-9]|1?[0-9]{1,2})(\.(25[0-5]|2[0-4][0-9]|1?[0-9]{1,2})){3}').setName("IPv4 address")
|
|
"IPv4 address (C{0.0.0.0 - 255.255.255.255})"
|
|
|
|
_ipv6_part = Regex(r'[0-9a-fA-F]{1,4}').setName("hex_integer")
|
|
_full_ipv6_address = (_ipv6_part + (':' + _ipv6_part)*7).setName("full IPv6 address")
|
|
_short_ipv6_address = (Optional(_ipv6_part + (':' + _ipv6_part)*(0,6)) + "::" + Optional(_ipv6_part + (':' + _ipv6_part)*(0,6))).setName("short IPv6 address")
|
|
_short_ipv6_address.addCondition(lambda t: sum(1 for tt in t if pyparsing_common._ipv6_part.matches(tt)) < 8)
|
|
_mixed_ipv6_address = ("::ffff:" + ipv4_address).setName("mixed IPv6 address")
|
|
ipv6_address = Combine((_full_ipv6_address | _mixed_ipv6_address | _short_ipv6_address).setName("IPv6 address")).setName("IPv6 address")
|
|
"IPv6 address (long, short, or mixed form)"
|
|
|
|
mac_address = Regex(r'[0-9a-fA-F]{2}([:.-])[0-9a-fA-F]{2}(?:\1[0-9a-fA-F]{2}){4}').setName("MAC address")
|
|
"MAC address xx:xx:xx:xx:xx (may also have '-' or '.' delimiters)"
|
|
|
|
@staticmethod
|
|
def convertToDate(fmt="%Y-%m-%d"):
|
|
"""
|
|
Helper to create a parse action for converting parsed date string to Python datetime.date
|
|
|
|
Params -
|
|
- fmt - format to be passed to datetime.strptime (default=C{"%Y-%m-%d"})
|
|
|
|
Example::
|
|
date_expr = pyparsing_common.iso8601_date.copy()
|
|
date_expr.setParseAction(pyparsing_common.convertToDate())
|
|
print(date_expr.parseString("1999-12-31"))
|
|
prints::
|
|
[datetime.date(1999, 12, 31)]
|
|
"""
|
|
def cvt_fn(s,l,t):
|
|
try:
|
|
return datetime.strptime(t[0], fmt).date()
|
|
except ValueError as ve:
|
|
raise ParseException(s, l, str(ve))
|
|
return cvt_fn
|
|
|
|
@staticmethod
|
|
def convertToDatetime(fmt="%Y-%m-%dT%H:%M:%S.%f"):
|
|
"""
|
|
Helper to create a parse action for converting parsed datetime string to Python datetime.datetime
|
|
|
|
Params -
|
|
- fmt - format to be passed to datetime.strptime (default=C{"%Y-%m-%dT%H:%M:%S.%f"})
|
|
|
|
Example::
|
|
dt_expr = pyparsing_common.iso8601_datetime.copy()
|
|
dt_expr.setParseAction(pyparsing_common.convertToDatetime())
|
|
print(dt_expr.parseString("1999-12-31T23:59:59.999"))
|
|
prints::
|
|
[datetime.datetime(1999, 12, 31, 23, 59, 59, 999000)]
|
|
"""
|
|
def cvt_fn(s,l,t):
|
|
try:
|
|
return datetime.strptime(t[0], fmt)
|
|
except ValueError as ve:
|
|
raise ParseException(s, l, str(ve))
|
|
return cvt_fn
|
|
|
|
iso8601_date = Regex(r'(?P<year>\d{4})(?:-(?P<month>\d\d)(?:-(?P<day>\d\d))?)?').setName("ISO8601 date")
|
|
"ISO8601 date (C{yyyy-mm-dd})"
|
|
|
|
iso8601_datetime = Regex(r'(?P<year>\d{4})-(?P<month>\d\d)-(?P<day>\d\d)[T ](?P<hour>\d\d):(?P<minute>\d\d)(:(?P<second>\d\d(\.\d*)?)?)?(?P<tz>Z|[+-]\d\d:?\d\d)?').setName("ISO8601 datetime")
|
|
"ISO8601 datetime (C{yyyy-mm-ddThh:mm:ss.s(Z|+-00:00)}) - trailing seconds, milliseconds, and timezone optional; accepts separating C{'T'} or C{' '}"
|
|
|
|
uuid = Regex(r'[0-9a-fA-F]{8}(-[0-9a-fA-F]{4}){3}-[0-9a-fA-F]{12}').setName("UUID")
|
|
"UUID (C{xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx})"
|
|
|
|
_html_stripper = anyOpenTag.suppress() | anyCloseTag.suppress()
|
|
@staticmethod
|
|
def stripHTMLTags(s, l, tokens):
|
|
"""
|
|
Parse action to remove HTML tags from web page HTML source
|
|
|
|
Example::
|
|
# strip HTML links from normal text
|
|
text = '<td>More info at the <a href="http://pyparsing.wikispaces.com">pyparsing</a> wiki page</td>'
|
|
td,td_end = makeHTMLTags("TD")
|
|
table_text = td + SkipTo(td_end).setParseAction(pyparsing_common.stripHTMLTags)("body") + td_end
|
|
|
|
print(table_text.parseString(text).body) # -> 'More info at the pyparsing wiki page'
|
|
"""
|
|
return pyparsing_common._html_stripper.transformString(tokens[0])
|
|
|
|
_commasepitem = Combine(OneOrMore(~Literal(",") + ~LineEnd() + Word(printables, excludeChars=',')
|
|
+ Optional( White(" \t") ) ) ).streamline().setName("commaItem")
|
|
comma_separated_list = delimitedList( Optional( quotedString.copy() | _commasepitem, default="") ).setName("comma separated list")
|
|
"""Predefined expression of 1 or more printable words or quoted strings, separated by commas."""
|
|
|
|
upcaseTokens = staticmethod(tokenMap(lambda t: _ustr(t).upper()))
|
|
"""Parse action to convert tokens to upper case."""
|
|
|
|
downcaseTokens = staticmethod(tokenMap(lambda t: _ustr(t).lower()))
|
|
"""Parse action to convert tokens to lower case."""
|
|
|
|
|
|
if __name__ == "__main__":
|
|
|
|
selectToken = CaselessLiteral("select")
|
|
fromToken = CaselessLiteral("from")
|
|
|
|
ident = Word(alphas, alphanums + "_$")
|
|
|
|
columnName = delimitedList(ident, ".", combine=True).setParseAction(upcaseTokens)
|
|
columnNameList = Group(delimitedList(columnName)).setName("columns")
|
|
columnSpec = ('*' | columnNameList)
|
|
|
|
tableName = delimitedList(ident, ".", combine=True).setParseAction(upcaseTokens)
|
|
tableNameList = Group(delimitedList(tableName)).setName("tables")
|
|
|
|
simpleSQL = selectToken("command") + columnSpec("columns") + fromToken + tableNameList("tables")
|
|
|
|
# demo runTests method, including embedded comments in test string
|
|
simpleSQL.runTests("""
|
|
# '*' as column list and dotted table name
|
|
select * from SYS.XYZZY
|
|
|
|
# caseless match on "SELECT", and casts back to "select"
|
|
SELECT * from XYZZY, ABC
|
|
|
|
# list of column names, and mixed case SELECT keyword
|
|
Select AA,BB,CC from Sys.dual
|
|
|
|
# multiple tables
|
|
Select A, B, C from Sys.dual, Table2
|
|
|
|
# invalid SELECT keyword - should fail
|
|
Xelect A, B, C from Sys.dual
|
|
|
|
# incomplete command - should fail
|
|
Select
|
|
|
|
# invalid column name - should fail
|
|
Select ^^^ frox Sys.dual
|
|
|
|
""")
|
|
|
|
pyparsing_common.number.runTests("""
|
|
100
|
|
-100
|
|
+100
|
|
3.14159
|
|
6.02e23
|
|
1e-12
|
|
""")
|
|
|
|
# any int or real number, returned as float
|
|
pyparsing_common.fnumber.runTests("""
|
|
100
|
|
-100
|
|
+100
|
|
3.14159
|
|
6.02e23
|
|
1e-12
|
|
""")
|
|
|
|
pyparsing_common.hex_integer.runTests("""
|
|
100
|
|
FF
|
|
""")
|
|
|
|
import uuid
|
|
pyparsing_common.uuid.setParseAction(tokenMap(uuid.UUID))
|
|
pyparsing_common.uuid.runTests("""
|
|
12345678-1234-5678-1234-567812345678
|
|
""")
|