mirror of
https://github.com/python/cpython.git
synced 2024-11-24 17:47:13 +01:00
b70ccc348b
this branch. While I am here, also get rid of other versionchanged:: 2.x constructs, as discussed.
160 lines
5.8 KiB
ReStructuredText
160 lines
5.8 KiB
ReStructuredText
.. highlightlang:: c
|
|
|
|
.. _setobjects:
|
|
|
|
Set Objects
|
|
-----------
|
|
|
|
.. sectionauthor:: Raymond D. Hettinger <python@rcn.com>
|
|
|
|
|
|
.. index::
|
|
object: set
|
|
object: frozenset
|
|
|
|
This section details the public API for :class:`set` and :class:`frozenset`
|
|
objects. Any functionality not listed below is best accessed using the either
|
|
the abstract object protocol (including :cfunc:`PyObject_CallMethod`,
|
|
:cfunc:`PyObject_RichCompareBool`, :cfunc:`PyObject_Hash`,
|
|
:cfunc:`PyObject_Repr`, :cfunc:`PyObject_IsTrue`, :cfunc:`PyObject_Print`, and
|
|
:cfunc:`PyObject_GetIter`) or the abstract number protocol (including
|
|
:cfunc:`PyNumber_And`, :cfunc:`PyNumber_Subtract`, :cfunc:`PyNumber_Or`,
|
|
:cfunc:`PyNumber_Xor`, :cfunc:`PyNumber_InPlaceAnd`,
|
|
:cfunc:`PyNumber_InPlaceSubtract`, :cfunc:`PyNumber_InPlaceOr`, and
|
|
:cfunc:`PyNumber_InPlaceXor`).
|
|
|
|
|
|
.. ctype:: PySetObject
|
|
|
|
This subtype of :ctype:`PyObject` is used to hold the internal data for both
|
|
:class:`set` and :class:`frozenset` objects. It is like a :ctype:`PyDictObject`
|
|
in that it is a fixed size for small sets (much like tuple storage) and will
|
|
point to a separate, variable sized block of memory for medium and large sized
|
|
sets (much like list storage). None of the fields of this structure should be
|
|
considered public and are subject to change. All access should be done through
|
|
the documented API rather than by manipulating the values in the structure.
|
|
|
|
|
|
.. cvar:: PyTypeObject PySet_Type
|
|
|
|
This is an instance of :ctype:`PyTypeObject` representing the Python
|
|
:class:`set` type.
|
|
|
|
|
|
.. cvar:: PyTypeObject PyFrozenSet_Type
|
|
|
|
This is an instance of :ctype:`PyTypeObject` representing the Python
|
|
:class:`frozenset` type.
|
|
|
|
The following type check macros work on pointers to any Python object. Likewise,
|
|
the constructor functions work with any iterable Python object.
|
|
|
|
|
|
.. cfunction:: int PySet_Check(PyObject *p)
|
|
|
|
Return true if *p* is a :class:`set` object or an instance of a subtype.
|
|
|
|
.. cfunction:: int PyFrozenSet_Check(PyObject *p)
|
|
|
|
Return true if *p* is a :class:`frozenset` object or an instance of a
|
|
subtype.
|
|
|
|
.. cfunction:: int PyAnySet_Check(PyObject *p)
|
|
|
|
Return true if *p* is a :class:`set` object, a :class:`frozenset` object, or an
|
|
instance of a subtype.
|
|
|
|
|
|
.. cfunction:: int PyAnySet_CheckExact(PyObject *p)
|
|
|
|
Return true if *p* is a :class:`set` object or a :class:`frozenset` object but
|
|
not an instance of a subtype.
|
|
|
|
|
|
.. cfunction:: int PyFrozenSet_CheckExact(PyObject *p)
|
|
|
|
Return true if *p* is a :class:`frozenset` object but not an instance of a
|
|
subtype.
|
|
|
|
|
|
.. cfunction:: PyObject* PySet_New(PyObject *iterable)
|
|
|
|
Return a new :class:`set` containing objects returned by the *iterable*. The
|
|
*iterable* may be *NULL* to create a new empty set. Return the new set on
|
|
success or *NULL* on failure. Raise :exc:`TypeError` if *iterable* is not
|
|
actually iterable. The constructor is also useful for copying a set
|
|
(``c=set(s)``).
|
|
|
|
|
|
.. cfunction:: PyObject* PyFrozenSet_New(PyObject *iterable)
|
|
|
|
Return a new :class:`frozenset` containing objects returned by the *iterable*.
|
|
The *iterable* may be *NULL* to create a new empty frozenset. Return the new
|
|
set on success or *NULL* on failure. Raise :exc:`TypeError` if *iterable* is
|
|
not actually iterable.
|
|
|
|
|
|
The following functions and macros are available for instances of :class:`set`
|
|
or :class:`frozenset` or instances of their subtypes.
|
|
|
|
|
|
.. cfunction:: Py_ssize_t PySet_Size(PyObject *anyset)
|
|
|
|
.. index:: builtin: len
|
|
|
|
Return the length of a :class:`set` or :class:`frozenset` object. Equivalent to
|
|
``len(anyset)``. Raises a :exc:`PyExc_SystemError` if *anyset* is not a
|
|
:class:`set`, :class:`frozenset`, or an instance of a subtype.
|
|
|
|
|
|
.. cfunction:: Py_ssize_t PySet_GET_SIZE(PyObject *anyset)
|
|
|
|
Macro form of :cfunc:`PySet_Size` without error checking.
|
|
|
|
|
|
.. cfunction:: int PySet_Contains(PyObject *anyset, PyObject *key)
|
|
|
|
Return 1 if found, 0 if not found, and -1 if an error is encountered. Unlike
|
|
the Python :meth:`__contains__` method, this function does not automatically
|
|
convert unhashable sets into temporary frozensets. Raise a :exc:`TypeError` if
|
|
the *key* is unhashable. Raise :exc:`PyExc_SystemError` if *anyset* is not a
|
|
:class:`set`, :class:`frozenset`, or an instance of a subtype.
|
|
|
|
|
|
.. cfunction:: int PySet_Add(PyObject *set, PyObject *key)
|
|
|
|
Add *key* to a :class:`set` instance. Also works with :class:`frozenset`
|
|
instances (like :cfunc:`PyTuple_SetItem` it can be used to fill-in the values
|
|
of brand new frozensets before they are exposed to other code). Return 0 on
|
|
success or -1 on failure. Raise a :exc:`TypeError` if the *key* is
|
|
unhashable. Raise a :exc:`MemoryError` if there is no room to grow. Raise a
|
|
:exc:`SystemError` if *set* is an not an instance of :class:`set` or its
|
|
subtype.
|
|
|
|
|
|
The following functions are available for instances of :class:`set` or its
|
|
subtypes but not for instances of :class:`frozenset` or its subtypes.
|
|
|
|
|
|
.. cfunction:: int PySet_Discard(PyObject *set, PyObject *key)
|
|
|
|
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:`discard`
|
|
method, this function does not automatically convert unhashable sets into
|
|
temporary frozensets. Raise :exc:`PyExc_SystemError` if *set* is an not an
|
|
instance of :class:`set` or its subtype.
|
|
|
|
|
|
.. cfunction:: PyObject* PySet_Pop(PyObject *set)
|
|
|
|
Return a new reference to an arbitrary object in the *set*, and removes the
|
|
object from the *set*. Return *NULL* on failure. Raise :exc:`KeyError` if the
|
|
set is empty. Raise a :exc:`SystemError` if *set* is an not an instance of
|
|
:class:`set` or its subtype.
|
|
|
|
|
|
.. cfunction:: int PySet_Clear(PyObject *set)
|
|
|
|
Empty an existing set of all elements.
|