CatOrNot/venv/lib/python3.6/site-packages/cachetools/keys.py
2018-12-11 00:32:28 +01:00

44 lines
1.0 KiB
Python

"""Key functions for memoizing decorators."""
from __future__ import absolute_import
__all__ = ('hashkey', 'typedkey')
class _HashedTuple(tuple):
__hashvalue = None
def __hash__(self, hash=tuple.__hash__):
hashvalue = self.__hashvalue
if hashvalue is None:
self.__hashvalue = hashvalue = hash(self)
return hashvalue
def __add__(self, other, add=tuple.__add__):
return _HashedTuple(add(self, other))
def __radd__(self, other, add=tuple.__add__):
return _HashedTuple(add(other, self))
_kwmark = (object(),)
def hashkey(*args, **kwargs):
"""Return a cache key for the specified hashable arguments."""
if kwargs:
return _HashedTuple(args + sum(sorted(kwargs.items()), _kwmark))
else:
return _HashedTuple(args)
def typedkey(*args, **kwargs):
"""Return a typed cache key for the specified hashable arguments."""
key = hashkey(*args, **kwargs)
key += tuple(type(v) for v in args)
key += tuple(type(v) for _, v in sorted(kwargs.items()))
return key