diff --git a/Doc/c-api/set.rst b/Doc/c-api/set.rst index cba823aa027..09c0fb6b9c5 100644 --- a/Doc/c-api/set.rst +++ b/Doc/c-api/set.rst @@ -147,7 +147,7 @@ subtypes but not for instances of :class:`frozenset` or its subtypes. Return ``1`` if found and removed, ``0`` if not found (no action taken), and ``-1`` if an error is encountered. Does not raise :exc:`KeyError` for missing keys. Raise a - :exc:`TypeError` if the *key* is unhashable. Unlike the Python :meth:`~frozenset.discard` + :exc:`TypeError` if the *key* is unhashable. Unlike the Python :meth:`~set.discard` method, this function does not automatically convert unhashable sets into temporary frozensets. Raise :exc:`SystemError` if *set* is not an instance of :class:`set` or its subtype. diff --git a/Doc/library/stdtypes.rst b/Doc/library/stdtypes.rst index cc5d1442b86..9bb903688bc 100644 --- a/Doc/library/stdtypes.rst +++ b/Doc/library/stdtypes.rst @@ -4802,7 +4802,7 @@ other sequence-like behavior. There are currently two built-in set types, :class:`set` and :class:`frozenset`. The :class:`set` type is mutable --- the contents can be changed using methods -like :meth:`add ` and :meth:`remove `. +like :meth:`~set.add` and :meth:`~set.remove`. Since it is mutable, it has no hash value and cannot be used as either a dictionary key or as an element of another set. The :class:`frozenset` type is immutable and :term:`hashable` --- @@ -4824,164 +4824,172 @@ The constructors for both classes work the same: objects. If *iterable* is not specified, a new empty set is returned. - Sets can be created by several means: +Sets can be created by several means: - * Use a comma-separated list of elements within braces: ``{'jack', 'sjoerd'}`` - * Use a set comprehension: ``{c for c in 'abracadabra' if c not in 'abc'}`` - * Use the type constructor: ``set()``, ``set('foobar')``, ``set(['a', 'b', 'foo'])`` +* Use a comma-separated list of elements within braces: ``{'jack', 'sjoerd'}`` +* Use a set comprehension: ``{c for c in 'abracadabra' if c not in 'abc'}`` +* Use the type constructor: ``set()``, ``set('foobar')``, ``set(['a', 'b', 'foo'])`` - Instances of :class:`set` and :class:`frozenset` provide the following - operations: +Instances of :class:`set` and :class:`frozenset` provide the following +operations: - .. describe:: len(s) +.. describe:: len(s) - Return the number of elements in set *s* (cardinality of *s*). + Return the number of elements in set *s* (cardinality of *s*). - .. describe:: x in s +.. describe:: x in s - Test *x* for membership in *s*. + Test *x* for membership in *s*. - .. describe:: x not in s +.. describe:: x not in s - Test *x* for non-membership in *s*. + Test *x* for non-membership in *s*. - .. method:: isdisjoint(other, /) +.. method:: frozenset.isdisjoint(other, /) + set.isdisjoint(other, /) - Return ``True`` if the set has no elements in common with *other*. Sets are - disjoint if and only if their intersection is the empty set. + Return ``True`` if the set has no elements in common with *other*. Sets are + disjoint if and only if their intersection is the empty set. - .. method:: issubset(other, /) - set <= other +.. method:: frozenset.issubset(other, /) + set.issubset(other, /) +.. describe:: set <= other - Test whether every element in the set is in *other*. + Test whether every element in the set is in *other*. - .. method:: set < other +.. describe:: set < other - Test whether the set is a proper subset of *other*, that is, - ``set <= other and set != other``. + Test whether the set is a proper subset of *other*, that is, + ``set <= other and set != other``. - .. method:: issuperset(other, /) - set >= other +.. method:: frozenset.issuperset(other, /) + set.issuperset(other, /) +.. describe:: set >= other - Test whether every element in *other* is in the set. + Test whether every element in *other* is in the set. - .. method:: set > other +.. describe:: set > other - Test whether the set is a proper superset of *other*, that is, ``set >= - other and set != other``. + Test whether the set is a proper superset of *other*, that is, ``set >= + other and set != other``. - .. method:: union(*others) - set | other | ... +.. method:: frozenset.union(*others) + set.union(*others) +.. describe:: set | other | ... - Return a new set with elements from the set and all others. + Return a new set with elements from the set and all others. - .. method:: intersection(*others) - set & other & ... +.. method:: frozenset.intersection(*others) + set.intersection(*others) +.. describe:: set & other & ... - Return a new set with elements common to the set and all others. + Return a new set with elements common to the set and all others. - .. method:: difference(*others) - set - other - ... +.. method:: frozenset.difference(*others) + set.difference(*others) +.. describe:: set - other - ... - Return a new set with elements in the set that are not in the others. + Return a new set with elements in the set that are not in the others. - .. method:: symmetric_difference(other, /) - set ^ other +.. method:: frozenset.symmetric_difference(other, /) + set.symmetric_difference(other, /) +.. describe:: set ^ other - Return a new set with elements in either the set or *other* but not both. + Return a new set with elements in either the set or *other* but not both. - .. method:: copy() +.. method:: frozenset.copy() + set.copy() - Return a shallow copy of the set. + Return a shallow copy of the set. - Note, the non-operator versions of :meth:`union`, :meth:`intersection`, - :meth:`difference`, :meth:`symmetric_difference`, :meth:`issubset`, and - :meth:`issuperset` methods will accept any iterable as an argument. In - contrast, their operator based counterparts require their arguments to be - sets. This precludes error-prone constructions like ``set('abc') & 'cbs'`` - in favor of the more readable ``set('abc').intersection('cbs')``. +Note, the non-operator versions of :meth:`~frozenset.union`, +:meth:`~frozenset.intersection`, :meth:`~frozenset.difference`, :meth:`~frozenset.symmetric_difference`, :meth:`~frozenset.issubset`, and +:meth:`~frozenset.issuperset` methods will accept any iterable as an argument. In +contrast, their operator based counterparts require their arguments to be +sets. This precludes error-prone constructions like ``set('abc') & 'cbs'`` +in favor of the more readable ``set('abc').intersection('cbs')``. - Both :class:`set` and :class:`frozenset` support set to set comparisons. Two - sets are equal if and only if every element of each set is contained in the - other (each is a subset of the other). A set is less than another set if and - only if the first set is a proper subset of the second set (is a subset, but - is not equal). A set is greater than another set if and only if the first set - is a proper superset of the second set (is a superset, but is not equal). +Both :class:`set` and :class:`frozenset` support set to set comparisons. Two +sets are equal if and only if every element of each set is contained in the +other (each is a subset of the other). A set is less than another set if and +only if the first set is a proper subset of the second set (is a subset, but +is not equal). A set is greater than another set if and only if the first set +is a proper superset of the second set (is a superset, but is not equal). - Instances of :class:`set` are compared to instances of :class:`frozenset` - based on their members. For example, ``set('abc') == frozenset('abc')`` - returns ``True`` and so does ``set('abc') in set([frozenset('abc')])``. +Instances of :class:`set` are compared to instances of :class:`frozenset` +based on their members. For example, ``set('abc') == frozenset('abc')`` +returns ``True`` and so does ``set('abc') in set([frozenset('abc')])``. - The subset and equality comparisons do not generalize to a total ordering - function. For example, any two nonempty disjoint sets are not equal and are not - subsets of each other, so *all* of the following return ``False``: ``ab``. +The subset and equality comparisons do not generalize to a total ordering +function. For example, any two nonempty disjoint sets are not equal and are not +subsets of each other, so *all* of the following return ``False``: ``ab``. - Since sets only define partial ordering (subset relationships), the output of - the :meth:`list.sort` method is undefined for lists of sets. +Since sets only define partial ordering (subset relationships), the output of +the :meth:`list.sort` method is undefined for lists of sets. - Set elements, like dictionary keys, must be :term:`hashable`. +Set elements, like dictionary keys, must be :term:`hashable`. - Binary operations that mix :class:`set` instances with :class:`frozenset` - return the type of the first operand. For example: ``frozenset('ab') | - set('bc')`` returns an instance of :class:`frozenset`. +Binary operations that mix :class:`set` instances with :class:`frozenset` +return the type of the first operand. For example: ``frozenset('ab') | +set('bc')`` returns an instance of :class:`frozenset`. - The following table lists operations available for :class:`set` that do not - apply to immutable instances of :class:`frozenset`: +The following table lists operations available for :class:`set` that do not +apply to immutable instances of :class:`frozenset`: - .. method:: update(*others) - set |= other | ... +.. method:: set.update(*others) +.. describe:: set |= other | ... - Update the set, adding elements from all others. + Update the set, adding elements from all others. - .. method:: intersection_update(*others) - set &= other & ... +.. method:: set.intersection_update(*others) +.. describe:: set &= other & ... - Update the set, keeping only elements found in it and all others. + Update the set, keeping only elements found in it and all others. - .. method:: difference_update(*others) - set -= other | ... +.. method:: set.difference_update(*others) +.. describe:: set -= other | ... - Update the set, removing elements found in others. + Update the set, removing elements found in others. - .. method:: symmetric_difference_update(other, /) - set ^= other +.. method:: set.symmetric_difference_update(other, /) +.. describe:: set ^= other - Update the set, keeping only elements found in either set, but not in both. + Update the set, keeping only elements found in either set, but not in both. - .. method:: add(elem, /) +.. method:: set.add(elem, /) - Add element *elem* to the set. + Add element *elem* to the set. - .. method:: remove(elem, /) +.. method:: set.remove(elem, /) - Remove element *elem* from the set. Raises :exc:`KeyError` if *elem* is - not contained in the set. + Remove element *elem* from the set. Raises :exc:`KeyError` if *elem* is + not contained in the set. - .. method:: discard(elem, /) +.. method:: set.discard(elem, /) - Remove element *elem* from the set if it is present. + Remove element *elem* from the set if it is present. - .. method:: pop() +.. method:: set.pop() - Remove and return an arbitrary element from the set. Raises - :exc:`KeyError` if the set is empty. + Remove and return an arbitrary element from the set. Raises + :exc:`KeyError` if the set is empty. - .. method:: clear() +.. method:: set.clear() - Remove all elements from the set. + Remove all elements from the set. - Note, the non-operator versions of the :meth:`update`, - :meth:`intersection_update`, :meth:`difference_update`, and - :meth:`symmetric_difference_update` methods will accept any iterable as an - argument. +Note, the non-operator versions of the :meth:`~set.update`, +:meth:`~set.intersection_update`, :meth:`~set.difference_update`, and +:meth:`~set.symmetric_difference_update` methods will accept any iterable as an +argument. - Note, the *elem* argument to the :meth:`~object.__contains__`, - :meth:`remove`, and - :meth:`discard` methods may be a set. To support searching for an equivalent - frozenset, a temporary one is created from *elem*. +Note, the *elem* argument to the :meth:`~object.__contains__`, +:meth:`~set.remove`, and +:meth:`~set.discard` methods may be a set. To support searching for an equivalent +frozenset, a temporary one is created from *elem*. .. _typesmapping: diff --git a/Doc/reference/datamodel.rst b/Doc/reference/datamodel.rst index e5c5cc2d5ef..71f669af76d 100644 --- a/Doc/reference/datamodel.rst +++ b/Doc/reference/datamodel.rst @@ -449,7 +449,7 @@ Sets These represent a mutable set. They are created by the built-in :func:`set` constructor and can be modified afterwards by several methods, such as - :meth:`add `. + :meth:`~set.add`. Frozen sets diff --git a/Doc/whatsnew/2.3.rst b/Doc/whatsnew/2.3.rst index b7e4e73f4ce..f43692b3dce 100644 --- a/Doc/whatsnew/2.3.rst +++ b/Doc/whatsnew/2.3.rst @@ -66,7 +66,7 @@ Here's a simple example:: The union and intersection of sets can be computed with the :meth:`~frozenset.union` and :meth:`~frozenset.intersection` methods; an alternative notation uses the bitwise operators ``&`` and ``|``. Mutable sets also have in-place versions of these methods, -:meth:`!union_update` and :meth:`~frozenset.intersection_update`. :: +:meth:`!union_update` and :meth:`~set.intersection_update`. :: >>> S1 = sets.Set([1,2,3]) >>> S2 = sets.Set([4,5,6]) @@ -87,7 +87,7 @@ It's also possible to take the symmetric difference of two sets. This is the set of all elements in the union that aren't in the intersection. Another way of putting it is that the symmetric difference contains all elements that are in exactly one set. Again, there's an alternative notation (``^``), and an -in-place version with the ungainly name :meth:`~frozenset.symmetric_difference_update`. :: +in-place version with the ungainly name :meth:`~set.symmetric_difference_update`. :: >>> S1 = sets.Set([1,2,3,4]) >>> S2 = sets.Set([3,4,5,6])