projektAI/venv/Lib/site-packages/pandas/core/indexes/frozen.py
2021-06-06 22:13:05 +02:00

110 lines
3.0 KiB
Python

"""
frozen (immutable) data structures to support MultiIndexing
These are used for:
- .names (FrozenList)
"""
from typing import Any
from pandas.core.base import PandasObject
from pandas.io.formats.printing import pprint_thing
class FrozenList(PandasObject, list):
"""
Container that doesn't allow setting item *but*
because it's technically non-hashable, will be used
for lookups, appropriately, etc.
"""
# Side note: This has to be of type list. Otherwise,
# it messes up PyTables type checks.
def union(self, other) -> "FrozenList":
"""
Returns a FrozenList with other concatenated to the end of self.
Parameters
----------
other : array-like
The array-like whose elements we are concatenating.
Returns
-------
FrozenList
The collection difference between self and other.
"""
if isinstance(other, tuple):
other = list(other)
return type(self)(super().__add__(other))
def difference(self, other) -> "FrozenList":
"""
Returns a FrozenList with elements from other removed from self.
Parameters
----------
other : array-like
The array-like whose elements we are removing self.
Returns
-------
FrozenList
The collection difference between self and other.
"""
other = set(other)
temp = [x for x in self if x not in other]
return type(self)(temp)
# TODO: Consider deprecating these in favor of `union` (xref gh-15506)
__add__ = __iadd__ = union
def __getitem__(self, n):
if isinstance(n, slice):
return type(self)(super().__getitem__(n))
return super().__getitem__(n)
def __radd__(self, other):
if isinstance(other, tuple):
other = list(other)
return type(self)(other + list(self))
def __eq__(self, other: Any) -> bool:
if isinstance(other, (tuple, FrozenList)):
other = list(other)
return super().__eq__(other)
__req__ = __eq__
def __mul__(self, other):
return type(self)(super().__mul__(other))
__imul__ = __mul__
def __reduce__(self):
return type(self), (list(self),)
def __hash__(self):
return hash(tuple(self))
def _disabled(self, *args, **kwargs):
"""
This method will not function because object is immutable.
"""
raise TypeError(f"'{type(self).__name__}' does not support mutable operations.")
def __str__(self) -> str:
return pprint_thing(self, quote_strings=True, escape_chars=("\t", "\r", "\n"))
def __repr__(self) -> str:
return f"{type(self).__name__}({str(self)})"
__setitem__ = __setslice__ = _disabled # type: ignore[assignment]
__delitem__ = __delslice__ = _disabled # type: ignore[assignment]
pop = append = extend = _disabled # type: ignore[assignment]
remove = sort = insert = _disabled # type: ignore[assignment]