diff options
Diffstat (limited to 'Lib/_collections_abc.py')
| -rw-r--r-- | Lib/_collections_abc.py | 30 |
1 files changed, 25 insertions, 5 deletions
diff --git a/Lib/_collections_abc.py b/Lib/_collections_abc.py index f89bb6f04b..31583731fc 100644 --- a/Lib/_collections_abc.py +++ b/Lib/_collections_abc.py @@ -10,7 +10,7 @@ from abc import ABCMeta, abstractmethod import sys __all__ = ["Awaitable", "Coroutine", "AsyncIterable", "AsyncIterator", - "Hashable", "Iterable", "Iterator", "Generator", + "Hashable", "Iterable", "Iterator", "Generator", "Reversible", "Sized", "Container", "Callable", "Set", "MutableSet", "Mapping", "MutableMapping", @@ -240,6 +240,25 @@ Iterator.register(tuple_iterator) Iterator.register(zip_iterator) +class Reversible(Iterable): + + __slots__ = () + + @abstractmethod + def __reversed__(self): + return NotImplemented + + @classmethod + def __subclasshook__(cls, C): + if cls is Reversible: + for B in C.__mro__: + if "__reversed__" in B.__dict__: + if B.__dict__["__reversed__"] is not None: + return True + break + return NotImplemented + + class Generator(Iterator): __slots__ = () @@ -670,7 +689,7 @@ class ItemsView(MappingView, Set): except KeyError: return False else: - return v == value + return v is value or v == value def __iter__(self): for key in self._mapping: @@ -685,7 +704,8 @@ class ValuesView(MappingView): def __contains__(self, value): for key in self._mapping: - if value == self._mapping[key]: + v = self._mapping[key] + if v is value or v == value: return True return False @@ -794,7 +814,7 @@ MutableMapping.register(dict) ### SEQUENCES ### -class Sequence(Sized, Iterable, Container): +class Sequence(Sized, Reversible, Container): """All the operations on a read-only sequence. @@ -820,7 +840,7 @@ class Sequence(Sized, Iterable, Container): def __contains__(self, value): for v in self: - if v == value: + if v is value or v == value: return True return False |