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Issue #18589: fix hyperlinking of type slots (tp_*)

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Antoine Pitrou 2013-08-01 21:12:45 +02:00
parent b3c872403d
commit 39668f57f4
9 changed files with 192 additions and 192 deletions
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6
Doc/c-api/allocation.rst
View file

@ -32,7 +32,7 @@ Allocating Objects on the Heap
Allocate a new Python object using the C structure type *TYPE* and the
Python type object *type*. Fields not defined by the Python object header
are not initialized; the object's reference count will be one. The size of
the memory allocation is determined from the :attr:`tp_basicsize` field of
the memory allocation is determined from the :c:member:`~PyTypeObject.tp_basicsize` field of
the type object.
@ -41,7 +41,7 @@ Allocating Objects on the Heap
Allocate a new Python object using the C structure type *TYPE* and the
Python type object *type*. Fields not defined by the Python object header
are not initialized. The allocated memory allows for the *TYPE* structure
plus *size* fields of the size given by the :attr:`tp_itemsize` field of
plus *size* fields of the size given by the :c:member:`~PyTypeObject.tp_itemsize` field of
*type*. This is useful for implementing objects like tuples, which are
able to determine their size at construction time. Embedding the array of
fields into the same allocation decreases the number of allocations,
@ -52,7 +52,7 @@ Allocating Objects on the Heap
Releases memory allocated to an object using :c:func:`PyObject_New` or
:c:func:`PyObject_NewVar`. This is normally called from the
:attr:`tp_dealloc` handler specified in the object's type. The fields of
:c:member:`~PyTypeObject.tp_dealloc` handler specified in the object's type. The fields of
the object should not be accessed after this call as the memory is no
longer a valid Python object.

12
Doc/c-api/exceptions.rst
View file

@ -607,28 +607,28 @@ recursion depth automatically).
Ends a :c:func:`Py_EnterRecursiveCall`. Must be called once for each
*successful* invocation of :c:func:`Py_EnterRecursiveCall`.
Properly implementing :attr:`tp_repr` for container types requires
Properly implementing :c:member:`~PyTypeObject.tp_repr` for container types requires
special recursion handling. In addition to protecting the stack,
:attr:`tp_repr` also needs to track objects to prevent cycles. The
:c:member:`~PyTypeObject.tp_repr` also needs to track objects to prevent cycles. The
following two functions facilitate this functionality. Effectively,
these are the C equivalent to :func:`reprlib.recursive_repr`.
.. c:function:: int Py_ReprEnter(PyObject *object)
Called at the beginning of the :attr:`tp_repr` implementation to
Called at the beginning of the :c:member:`~PyTypeObject.tp_repr` implementation to
detect cycles.
If the object has already been processed, the function returns a
positive integer. In that case the :attr:`tp_repr` implementation
positive integer. In that case the :c:member:`~PyTypeObject.tp_repr` implementation
should return a string object indicating a cycle. As examples,
:class:`dict` objects return ``{...}`` and :class:`list` objects
return ``[...]``.
The function will return a negative integer if the recursion limit
is reached. In that case the :attr:`tp_repr` implementation should
is reached. In that case the :c:member:`~PyTypeObject.tp_repr` implementation should
typically return ``NULL``.
Otherwise, the function returns zero and the :attr:`tp_repr`
Otherwise, the function returns zero and the :c:member:`~PyTypeObject.tp_repr`
implementation can continue normally.
.. c:function:: void Py_ReprLeave(PyObject *object)

28
Doc/c-api/gcsupport.rst
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@ -12,10 +12,10 @@ other objects, or which only store references to atomic types (such as numbers
or strings), do not need to provide any explicit support for garbage
collection.
To create a container type, the :attr:`tp_flags` field of the type object must
To create a container type, the :c:member:`~PyTypeObject.tp_flags` field of the type object must
include the :const:`Py_TPFLAGS_HAVE_GC` and provide an implementation of the
:attr:`tp_traverse` handler. If instances of the type are mutable, a
:attr:`tp_clear` implementation must also be provided.
:c:member:`~PyTypeObject.tp_traverse` handler. If instances of the type are mutable, a
:c:member:`~PyTypeObject.tp_clear` implementation must also be provided.
.. data:: Py_TPFLAGS_HAVE_GC
@ -57,7 +57,7 @@ Constructors for container types must conform to two rules:
Adds the object *op* to the set of container objects tracked by the
collector. The collector can run at unexpected times so objects must be
valid while being tracked. This should be called once all the fields
followed by the :attr:`tp_traverse` handler become valid, usually near the
followed by the :c:member:`~PyTypeObject.tp_traverse` handler become valid, usually near the
end of the constructor.
@ -86,8 +86,8 @@ rules:
Remove the object *op* from the set of container objects tracked by the
collector. Note that :c:func:`PyObject_GC_Track` can be called again on
this object to add it back to the set of tracked objects. The deallocator
(:attr:`tp_dealloc` handler) should call this for the object before any of
the fields used by the :attr:`tp_traverse` handler become invalid.
(:c:member:`~PyTypeObject.tp_dealloc` handler) should call this for the object before any of
the fields used by the :c:member:`~PyTypeObject.tp_traverse` handler become invalid.
.. c:function:: void _PyObject_GC_UNTRACK(PyObject *op)
@ -95,19 +95,19 @@ rules:
A macro version of :c:func:`PyObject_GC_UnTrack`. It should not be used for
extension modules.
The :attr:`tp_traverse` handler accepts a function parameter of this type:
The :c:member:`~PyTypeObject.tp_traverse` handler accepts a function parameter of this type:
.. c:type:: int (*visitproc)(PyObject *object, void *arg)
Type of the visitor function passed to the :attr:`tp_traverse` handler.
Type of the visitor function passed to the :c:member:`~PyTypeObject.tp_traverse` handler.
The function should be called with an object to traverse as *object* and
the third parameter to the :attr:`tp_traverse` handler as *arg*. The
the third parameter to the :c:member:`~PyTypeObject.tp_traverse` handler as *arg*. The
Python core uses several visitor functions to implement cyclic garbage
detection; it's not expected that users will need to write their own
visitor functions.
The :attr:`tp_traverse` handler must have the following type:
The :c:member:`~PyTypeObject.tp_traverse` handler must have the following type:
.. c:type:: int (*traverseproc)(PyObject *self, visitproc visit, void *arg)
@ -119,15 +119,15 @@ The :attr:`tp_traverse` handler must have the following type:
object argument. If *visit* returns a non-zero value that value should be
returned immediately.
To simplify writing :attr:`tp_traverse` handlers, a :c:func:`Py_VISIT` macro is
provided. In order to use this macro, the :attr:`tp_traverse` implementation
To simplify writing :c:member:`~PyTypeObject.tp_traverse` handlers, a :c:func:`Py_VISIT` macro is
provided. In order to use this macro, the :c:member:`~PyTypeObject.tp_traverse` implementation
must name its arguments exactly *visit* and *arg*:
.. c:function:: void Py_VISIT(PyObject *o)
Call the *visit* callback, with arguments *o* and *arg*. If *visit* returns
a non-zero value, then return it. Using this macro, :attr:`tp_traverse`
a non-zero value, then return it. Using this macro, :c:member:`~PyTypeObject.tp_traverse`
handlers look like::
static int
@ -138,7 +138,7 @@ must name its arguments exactly *visit* and *arg*:
return 0;
}
The :attr:`tp_clear` handler must be of the :c:type:`inquiry` type, or *NULL*
The :c:member:`~PyTypeObject.tp_clear` handler must be of the :c:type:`inquiry` type, or *NULL*
if the object is immutable.

10
Doc/c-api/type.rst
View file

@ -37,10 +37,10 @@ Type Objects
.. c:function:: long PyType_GetFlags(PyTypeObject* type)
Return the :attr:`tp_flags` member of *type*. This function is primarily
Return the :c:member:`~PyTypeObject.tp_flags` member of *type*. This function is primarily
meant for use with `Py_LIMITED_API`; the individual flag bits are
guaranteed to be stable across Python releases, but access to
:attr:`tp_flags` itself is not part of the limited API.
:c:member:`~PyTypeObject.tp_flags` itself is not part of the limited API.
.. versionadded:: 3.2
@ -70,14 +70,14 @@ Type Objects
.. c:function:: PyObject* PyType_GenericAlloc(PyTypeObject *type, Py_ssize_t nitems)
Generic handler for the :attr:`tp_alloc` slot of a type object. Use
Generic handler for the :c:member:`~PyTypeObject.tp_alloc` slot of a type object. Use
Python's default memory allocation mechanism to allocate a new instance and
initialize all its contents to *NULL*.
.. c:function:: PyObject* PyType_GenericNew(PyTypeObject *type, PyObject *args, PyObject *kwds)
Generic handler for the :attr:`tp_new` slot of a type object. Create a
new instance using the type's :attr:`tp_alloc` slot.
Generic handler for the :c:member:`~PyTypeObject.tp_new` slot of a type object. Create a
new instance using the type's :c:member:`~PyTypeObject.tp_alloc` slot.
.. c:function:: int PyType_Ready(PyTypeObject *type)

218
Doc/c-api/typeobj.rst
View file

@ -35,7 +35,7 @@ definition found there:
The type object structure extends the :c:type:`PyVarObject` structure. The
:attr:`ob_size` field is used for dynamic types (created by :func:`type_new`,
usually called from a class statement). Note that :c:data:`PyType_Type` (the
metatype) initializes :attr:`tp_itemsize`, which means that its instances (i.e.
metatype) initializes :c:member:`~PyTypeObject.tp_itemsize`, which means that its instances (i.e.
type objects) *must* have the :attr:`ob_size` field.
@ -102,7 +102,7 @@ type objects) *must* have the :attr:`ob_size` field.
should be just the type name. If the module is a submodule of a package, the
full package name is part of the full module name. For example, a type named
:class:`T` defined in module :mod:`M` in subpackage :mod:`Q` in package :mod:`P`
should have the :attr:`tp_name` initializer ``"P.Q.M.T"``.
should have the :c:member:`~PyTypeObject.tp_name` initializer ``"P.Q.M.T"``.
For dynamically allocated type objects, this should just be the type name, and
the module name explicitly stored in the type dict as the value for key
@ -113,7 +113,7 @@ type objects) *must* have the :attr:`ob_size` field.
attribute, and everything after the last dot is made accessible as the
:attr:`__name__` attribute.
If no dot is present, the entire :attr:`tp_name` field is made accessible as the
If no dot is present, the entire :c:member:`~PyTypeObject.tp_name` field is made accessible as the
:attr:`__name__` attribute, and the :attr:`__module__` attribute is undefined
(unless explicitly set in the dictionary, as explained above). This means your
type will be impossible to pickle.
@ -127,13 +127,13 @@ type objects) *must* have the :attr:`ob_size` field.
These fields allow calculating the size in bytes of instances of the type.
There are two kinds of types: types with fixed-length instances have a zero
:attr:`tp_itemsize` field, types with variable-length instances have a non-zero
:attr:`tp_itemsize` field. For a type with fixed-length instances, all
instances have the same size, given in :attr:`tp_basicsize`.
:c:member:`~PyTypeObject.tp_itemsize` field, types with variable-length instances have a non-zero
:c:member:`~PyTypeObject.tp_itemsize` field. For a type with fixed-length instances, all
instances have the same size, given in :c:member:`~PyTypeObject.tp_basicsize`.
For a type with variable-length instances, the instances must have an
:attr:`ob_size` field, and the instance size is :attr:`tp_basicsize` plus N
times :attr:`tp_itemsize`, where N is the "length" of the object. The value of
:attr:`ob_size` field, and the instance size is :c:member:`~PyTypeObject.tp_basicsize` plus N
times :c:member:`~PyTypeObject.tp_itemsize`, where N is the "length" of the object. The value of
N is typically stored in the instance's :attr:`ob_size` field. There are
exceptions: for example, ints use a negative :attr:`ob_size` to indicate a
negative number, and N is ``abs(ob_size)`` there. Also, the presence of an
@ -146,20 +146,20 @@ type objects) *must* have the :attr:`ob_size` field.
:c:macro:`PyObject_HEAD` or :c:macro:`PyObject_VAR_HEAD` (whichever is used to
declare the instance struct) and this in turn includes the :attr:`_ob_prev` and
:attr:`_ob_next` fields if they are present. This means that the only correct
way to get an initializer for the :attr:`tp_basicsize` is to use the
way to get an initializer for the :c:member:`~PyTypeObject.tp_basicsize` is to use the
``sizeof`` operator on the struct used to declare the instance layout.
The basic size does not include the GC header size.
These fields are inherited separately by subtypes. If the base type has a
non-zero :attr:`tp_itemsize`, it is generally not safe to set
:attr:`tp_itemsize` to a different non-zero value in a subtype (though this
non-zero :c:member:`~PyTypeObject.tp_itemsize`, it is generally not safe to set
:c:member:`~PyTypeObject.tp_itemsize` to a different non-zero value in a subtype (though this
depends on the implementation of the base type).
A note about alignment: if the variable items require a particular alignment,
this should be taken care of by the value of :attr:`tp_basicsize`. Example:
suppose a type implements an array of ``double``. :attr:`tp_itemsize` is
this should be taken care of by the value of :c:member:`~PyTypeObject.tp_basicsize`. Example:
suppose a type implements an array of ``double``. :c:member:`~PyTypeObject.tp_itemsize` is
``sizeof(double)``. It is the programmer's responsibility that
:attr:`tp_basicsize` is a multiple of ``sizeof(double)`` (assuming this is the
:c:member:`~PyTypeObject.tp_basicsize` is a multiple of ``sizeof(double)`` (assuming this is the
alignment requirement for ``double``).
@ -175,10 +175,10 @@ type objects) *must* have the :attr:`ob_size` field.
destructor function should free all references which the instance owns, free all
memory buffers owned by the instance (using the freeing function corresponding
to the allocation function used to allocate the buffer), and finally (as its
last action) call the type's :attr:`tp_free` function. If the type is not
last action) call the type's :c:member:`~PyTypeObject.tp_free` function. If the type is not
subtypable (doesn't have the :const:`Py_TPFLAGS_BASETYPE` flag bit set), it is
permissible to call the object deallocator directly instead of via
:attr:`tp_free`. The object deallocator should be the one used to allocate the
:c:member:`~PyTypeObject.tp_free`. The object deallocator should be the one used to allocate the
instance; this is normally :c:func:`PyObject_Del` if the instance was allocated
using :c:func:`PyObject_New` or :c:func:`PyObject_VarNew`, or
:c:func:`PyObject_GC_Del` if the instance was allocated using
@ -193,25 +193,25 @@ type objects) *must* have the :attr:`ob_size` field.
The print function is only called when the instance is printed to a *real* file;
when it is printed to a pseudo-file (like a :class:`StringIO` instance), the
instance's :attr:`tp_repr` or :attr:`tp_str` function is called to convert it to
a string. These are also called when the type's :attr:`tp_print` field is
*NULL*. A type should never implement :attr:`tp_print` in a way that produces
different output than :attr:`tp_repr` or :attr:`tp_str` would.
instance's :c:member:`~PyTypeObject.tp_repr` or :c:member:`~PyTypeObject.tp_str` function is called to convert it to
a string. These are also called when the type's :c:member:`~PyTypeObject.tp_print` field is
*NULL*. A type should never implement :c:member:`~PyTypeObject.tp_print` in a way that produces
different output than :c:member:`~PyTypeObject.tp_repr` or :c:member:`~PyTypeObject.tp_str` would.
The print function is called with the same signature as :c:func:`PyObject_Print`:
``int tp_print(PyObject *self, FILE *file, int flags)``. The *self* argument is
the instance to be printed. The *file* argument is the stdio file to which it
is to be printed. The *flags* argument is composed of flag bits. The only flag
bit currently defined is :const:`Py_PRINT_RAW`. When the :const:`Py_PRINT_RAW`
flag bit is set, the instance should be printed the same way as :attr:`tp_str`
flag bit is set, the instance should be printed the same way as :c:member:`~PyTypeObject.tp_str`
would format it; when the :const:`Py_PRINT_RAW` flag bit is clear, the instance
should be printed the same was as :attr:`tp_repr` would format it. It should
should be printed the same was as :c:member:`~PyTypeObject.tp_repr` would format it. It should
return ``-1`` and set an exception condition when an error occurred during the
comparison.
It is possible that the :attr:`tp_print` field will be deprecated. In any case,
it is recommended not to define :attr:`tp_print`, but instead to rely on
:attr:`tp_repr` and :attr:`tp_str` for printing.
It is possible that the :c:member:`~PyTypeObject.tp_print` field will be deprecated. In any case,
it is recommended not to define :c:member:`~PyTypeObject.tp_print`, but instead to rely on
:c:member:`~PyTypeObject.tp_repr` and :c:member:`~PyTypeObject.tp_str` for printing.
This field is inherited by subtypes.
@ -221,13 +221,13 @@ type objects) *must* have the :attr:`ob_size` field.
An optional pointer to the get-attribute-string function.
This field is deprecated. When it is defined, it should point to a function
that acts the same as the :attr:`tp_getattro` function, but taking a C string
that acts the same as the :c:member:`~PyTypeObject.tp_getattro` function, but taking a C string
instead of a Python string object to give the attribute name. The signature is
the same as for :c:func:`PyObject_GetAttrString`.
This field is inherited by subtypes together with :attr:`tp_getattro`: a subtype
inherits both :attr:`tp_getattr` and :attr:`tp_getattro` from its base type when
the subtype's :attr:`tp_getattr` and :attr:`tp_getattro` are both *NULL*.
This field is inherited by subtypes together with :c:member:`~PyTypeObject.tp_getattro`: a subtype
inherits both :c:member:`~PyTypeObject.tp_getattr` and :c:member:`~PyTypeObject.tp_getattro` from its base type when
the subtype's :c:member:`~PyTypeObject.tp_getattr` and :c:member:`~PyTypeObject.tp_getattro` are both *NULL*.
.. c:member:: setattrfunc PyTypeObject.tp_setattr
@ -235,13 +235,13 @@ type objects) *must* have the :attr:`ob_size` field.
An optional pointer to the set-attribute-string function.
This field is deprecated. When it is defined, it should point to a function
that acts the same as the :attr:`tp_setattro` function, but taking a C string
that acts the same as the :c:member:`~PyTypeObject.tp_setattro` function, but taking a C string
instead of a Python string object to give the attribute name. The signature is
the same as for :c:func:`PyObject_SetAttrString`.
This field is inherited by subtypes together with :attr:`tp_setattro`: a subtype
inherits both :attr:`tp_setattr` and :attr:`tp_setattro` from its base type when
the subtype's :attr:`tp_setattr` and :attr:`tp_setattro` are both *NULL*.
This field is inherited by subtypes together with :c:member:`~PyTypeObject.tp_setattro`: a subtype
inherits both :c:member:`~PyTypeObject.tp_setattr` and :c:member:`~PyTypeObject.tp_setattro` from its base type when
the subtype's :c:member:`~PyTypeObject.tp_setattr` and :c:member:`~PyTypeObject.tp_setattro` are both *NULL*.
.. c:member:: void* PyTypeObject.tp_reserved
@ -275,7 +275,7 @@ type objects) *must* have the :attr:`ob_size` field.
objects which implement the number protocol. These fields are documented in
:ref:`number-structs`.
The :attr:`tp_as_number` field is not inherited, but the contained fields are
The :c:member:`~PyTypeObject.tp_as_number` field is not inherited, but the contained fields are
inherited individually.
@ -285,7 +285,7 @@ type objects) *must* have the :attr:`ob_size` field.
objects which implement the sequence protocol. These fields are documented
in :ref:`sequence-structs`.
The :attr:`tp_as_sequence` field is not inherited, but the contained fields
The :c:member:`~PyTypeObject.tp_as_sequence` field is not inherited, but the contained fields
are inherited individually.
@ -295,7 +295,7 @@ type objects) *must* have the :attr:`ob_size` field.
objects which implement the mapping protocol. These fields are documented in
:ref:`mapping-structs`.
The :attr:`tp_as_mapping` field is not inherited, but the contained fields
The :c:member:`~PyTypeObject.tp_as_mapping` field is not inherited, but the contained fields
are inherited individually.
@ -323,9 +323,9 @@ type objects) *must* have the :attr:`ob_size` field.
object raises :exc:`TypeError`.
This field is inherited by subtypes together with
:attr:`tp_richcompare`: a subtype inherits both of
:attr:`tp_richcompare` and :attr:`tp_hash`, when the subtype's
:attr:`tp_richcompare` and :attr:`tp_hash` are both *NULL*.
:c:member:`~PyTypeObject.tp_richcompare`: a subtype inherits both of
:c:member:`~PyTypeObject.tp_richcompare` and :c:member:`~PyTypeObject.tp_hash`, when the subtype's
:c:member:`~PyTypeObject.tp_richcompare` and :c:member:`~PyTypeObject.tp_hash` are both *NULL*.
.. c:member:: ternaryfunc PyTypeObject.tp_call
@ -363,9 +363,9 @@ type objects) *must* have the :attr:`ob_size` field.
convenient to set this field to :c:func:`PyObject_GenericGetAttr`, which
implements the normal way of looking for object attributes.
This field is inherited by subtypes together with :attr:`tp_getattr`: a subtype
inherits both :attr:`tp_getattr` and :attr:`tp_getattro` from its base type when
the subtype's :attr:`tp_getattr` and :attr:`tp_getattro` are both *NULL*.
This field is inherited by subtypes together with :c:member:`~PyTypeObject.tp_getattr`: a subtype
inherits both :c:member:`~PyTypeObject.tp_getattr` and :c:member:`~PyTypeObject.tp_getattro` from its base type when
the subtype's :c:member:`~PyTypeObject.tp_getattr` and :c:member:`~PyTypeObject.tp_getattro` are both *NULL*.
.. c:member:: setattrofunc PyTypeObject.tp_setattro
@ -376,9 +376,9 @@ type objects) *must* have the :attr:`ob_size` field.
convenient to set this field to :c:func:`PyObject_GenericSetAttr`, which
implements the normal way of setting object attributes.
This field is inherited by subtypes together with :attr:`tp_setattr`: a subtype
inherits both :attr:`tp_setattr` and :attr:`tp_setattro` from its base type when
the subtype's :attr:`tp_setattr` and :attr:`tp_setattro` are both *NULL*.
This field is inherited by subtypes together with :c:member:`~PyTypeObject.tp_setattr`: a subtype
inherits both :c:member:`~PyTypeObject.tp_setattr` and :c:member:`~PyTypeObject.tp_setattro` from its base type when
the subtype's :c:member:`~PyTypeObject.tp_setattr` and :c:member:`~PyTypeObject.tp_setattro` are both *NULL*.
.. c:member:: PyBufferProcs* PyTypeObject.tp_as_buffer
@ -387,7 +387,7 @@ type objects) *must* have the :attr:`ob_size` field.
which implement the buffer interface. These fields are documented in
:ref:`buffer-structs`.
The :attr:`tp_as_buffer` field is not inherited, but the contained fields are
The :c:member:`~PyTypeObject.tp_as_buffer` field is not inherited, but the contained fields are
inherited individually.
@ -396,8 +396,8 @@ type objects) *must* have the :attr:`ob_size` field.
This field is a bit mask of various flags. Some flags indicate variant
semantics for certain situations; others are used to indicate that certain
fields in the type object (or in the extension structures referenced via
:attr:`tp_as_number`, :attr:`tp_as_sequence`, :attr:`tp_as_mapping`, and
:attr:`tp_as_buffer`) that were historically not always present are valid; if
:c:member:`~PyTypeObject.tp_as_number`, :c:member:`~PyTypeObject.tp_as_sequence`, :c:member:`~PyTypeObject.tp_as_mapping`, and
:c:member:`~PyTypeObject.tp_as_buffer`) that were historically not always present are valid; if
such a flag bit is clear, the type fields it guards must not be accessed and
must be considered to have a zero or *NULL* value instead.
@ -407,13 +407,13 @@ type objects) *must* have the :attr:`ob_size` field.
inherited if the extension structure is inherited, i.e. the base type's value of
the flag bit is copied into the subtype together with a pointer to the extension
structure. The :const:`Py_TPFLAGS_HAVE_GC` flag bit is inherited together with
the :attr:`tp_traverse` and :attr:`tp_clear` fields, i.e. if the
the :c:member:`~PyTypeObject.tp_traverse` and :c:member:`~PyTypeObject.tp_clear` fields, i.e. if the
:const:`Py_TPFLAGS_HAVE_GC` flag bit is clear in the subtype and the
:attr:`tp_traverse` and :attr:`tp_clear` fields in the subtype exist and have
:c:member:`~PyTypeObject.tp_traverse` and :c:member:`~PyTypeObject.tp_clear` fields in the subtype exist and have
*NULL* values.
The following bit masks are currently defined; these can be ORed together using
the ``|`` operator to form the value of the :attr:`tp_flags` field. The macro
the ``|`` operator to form the value of the :c:member:`~PyTypeObject.tp_flags` field. The macro
:c:func:`PyType_HasFeature` takes a type and a flags value, *tp* and *f*, and
checks whether ``tp->tp_flags & f`` is non-zero.
@ -453,7 +453,7 @@ type objects) *must* have the :attr:`ob_size` field.
is set, instances must be created using :c:func:`PyObject_GC_New` and
destroyed using :c:func:`PyObject_GC_Del`. More information in section
:ref:`supporting-cycle-detection`. This bit also implies that the
GC-related fields :attr:`tp_traverse` and :attr:`tp_clear` are present in
GC-related fields :c:member:`~PyTypeObject.tp_traverse` and :c:member:`~PyTypeObject.tp_clear` are present in
the type object.
@ -481,8 +481,8 @@ type objects) *must* have the :attr:`ob_size` field.
about Python's garbage collection scheme can be found in section
:ref:`supporting-cycle-detection`.
The :attr:`tp_traverse` pointer is used by the garbage collector to detect
reference cycles. A typical implementation of a :attr:`tp_traverse` function
The :c:member:`~PyTypeObject.tp_traverse` pointer is used by the garbage collector to detect
reference cycles. A typical implementation of a :c:member:`~PyTypeObject.tp_traverse` function
simply calls :c:func:`Py_VISIT` on each of the instance's members that are Python
objects. For example, this is function :c:func:`local_traverse` from the
:mod:`_thread` extension module::
@ -508,9 +508,9 @@ type objects) *must* have the :attr:`ob_size` field.
:c:func:`local_traverse` to have these specific names; don't name them just
anything.
This field is inherited by subtypes together with :attr:`tp_clear` and the
:const:`Py_TPFLAGS_HAVE_GC` flag bit: the flag bit, :attr:`tp_traverse`, and
:attr:`tp_clear` are all inherited from the base type if they are all zero in
This field is inherited by subtypes together with :c:member:`~PyTypeObject.tp_clear` and the
:const:`Py_TPFLAGS_HAVE_GC` flag bit: the flag bit, :c:member:`~PyTypeObject.tp_traverse`, and
:c:member:`~PyTypeObject.tp_clear` are all inherited from the base type if they are all zero in
the subtype.
@ -519,17 +519,17 @@ type objects) *must* have the :attr:`ob_size` field.
An optional pointer to a clear function for the garbage collector. This is only
used if the :const:`Py_TPFLAGS_HAVE_GC` flag bit is set.
The :attr:`tp_clear` member function is used to break reference cycles in cyclic
garbage detected by the garbage collector. Taken together, all :attr:`tp_clear`
The :c:member:`~PyTypeObject.tp_clear` member function is used to break reference cycles in cyclic
garbage detected by the garbage collector. Taken together, all :c:member:`~PyTypeObject.tp_clear`
functions in the system must combine to break all reference cycles. This is
subtle, and if in any doubt supply a :attr:`tp_clear` function. For example,
the tuple type does not implement a :attr:`tp_clear` function, because it's
subtle, and if in any doubt supply a :c:member:`~PyTypeObject.tp_clear` function. For example,
the tuple type does not implement a :c:member:`~PyTypeObject.tp_clear` function, because it's
possible to prove that no reference cycle can be composed entirely of tuples.
Therefore the :attr:`tp_clear` functions of other types must be sufficient to
Therefore the :c:member:`~PyTypeObject.tp_clear` functions of other types must be sufficient to
break any cycle containing a tuple. This isn't immediately obvious, and there's
rarely a good reason to avoid implementing :attr:`tp_clear`.
rarely a good reason to avoid implementing :c:member:`~PyTypeObject.tp_clear`.
Implementations of :attr:`tp_clear` should drop the instance's references to
Implementations of :c:member:`~PyTypeObject.tp_clear` should drop the instance's references to
those of its members that may be Python objects, and set its pointers to those
members to *NULL*, as in the following example::
@ -554,18 +554,18 @@ type objects) *must* have the :attr:`ob_size` field.
so that *self* knows the contained object can no longer be used. The
:c:func:`Py_CLEAR` macro performs the operations in a safe order.
Because the goal of :attr:`tp_clear` functions is to break reference cycles,
Because the goal of :c:member:`~PyTypeObject.tp_clear` functions is to break reference cycles,
it's not necessary to clear contained objects like Python strings or Python
integers, which can't participate in reference cycles. On the other hand, it may
be convenient to clear all contained Python objects, and write the type's
:attr:`tp_dealloc` function to invoke :attr:`tp_clear`.
:c:member:`~PyTypeObject.tp_dealloc` function to invoke :c:member:`~PyTypeObject.tp_clear`.
More information about Python's garbage collection scheme can be found in
section :ref:`supporting-cycle-detection`.
This field is inherited by subtypes together with :attr:`tp_traverse` and the
:const:`Py_TPFLAGS_HAVE_GC` flag bit: the flag bit, :attr:`tp_traverse`, and
:attr:`tp_clear` are all inherited from the base type if they are all zero in
This field is inherited by subtypes together with :c:member:`~PyTypeObject.tp_traverse` and the
:const:`Py_TPFLAGS_HAVE_GC` flag bit: the flag bit, :c:member:`~PyTypeObject.tp_traverse`, and
:c:member:`~PyTypeObject.tp_clear` are all inherited from the base type if they are all zero in
the subtype.
@ -585,13 +585,13 @@ type objects) *must* have the :attr:`ob_size` field.
comparisons makes sense (e.g. ``==`` and ``!=``, but not ``<`` and
friends), directly raise :exc:`TypeError` in the rich comparison function.
This field is inherited by subtypes together with :attr:`tp_hash`:
a subtype inherits :attr:`tp_richcompare` and :attr:`tp_hash` when
the subtype's :attr:`tp_richcompare` and :attr:`tp_hash` are both
This field is inherited by subtypes together with :c:member:`~PyTypeObject.tp_hash`:
a subtype inherits :c:member:`~PyTypeObject.tp_richcompare` and :c:member:`~PyTypeObject.tp_hash` when
the subtype's :c:member:`~PyTypeObject.tp_richcompare` and :c:member:`~PyTypeObject.tp_hash` are both
*NULL*.
The following constants are defined to be used as the third argument for
:attr:`tp_richcompare` and for :c:func:`PyObject_RichCompare`:
:c:member:`~PyTypeObject.tp_richcompare` and for :c:func:`PyObject_RichCompare`:
+----------------+------------+
| Constant | Comparison |
@ -619,26 +619,26 @@ type objects) *must* have the :attr:`ob_size` field.
instance structure needs to include a field of type :c:type:`PyObject\*` which is
initialized to *NULL*.
Do not confuse this field with :attr:`tp_weaklist`; that is the list head for
Do not confuse this field with :c:member:`~PyTypeObject.tp_weaklist`; that is the list head for
weak references to the type object itself.
This field is inherited by subtypes, but see the rules listed below. A subtype
may override this offset; this means that the subtype uses a different weak
reference list head than the base type. Since the list head is always found via
:attr:`tp_weaklistoffset`, this should not be a problem.
:c:member:`~PyTypeObject.tp_weaklistoffset`, this should not be a problem.
When a type defined by a class statement has no :attr:`__slots__` declaration,
and none of its base types are weakly referenceable, the type is made weakly
referenceable by adding a weak reference list head slot to the instance layout
and setting the :attr:`tp_weaklistoffset` of that slot's offset.
and setting the :c:member:`~PyTypeObject.tp_weaklistoffset` of that slot's offset.
When a type's :attr:`__slots__` declaration contains a slot named
:attr:`__weakref__`, that slot becomes the weak reference list head for
instances of the type, and the slot's offset is stored in the type's
:attr:`tp_weaklistoffset`.
:c:member:`~PyTypeObject.tp_weaklistoffset`.
When a type's :attr:`__slots__` declaration does not contain a slot named
:attr:`__weakref__`, the type inherits its :attr:`tp_weaklistoffset` from its
:attr:`__weakref__`, the type inherits its :c:member:`~PyTypeObject.tp_weaklistoffset` from its
base type.
.. c:member:: getiterfunc PyTypeObject.tp_iter
@ -660,7 +660,7 @@ type objects) *must* have the :attr:`ob_size` field.
*NULL* too. Its presence signals that the instances of this type are
iterators.
Iterator types should also define the :attr:`tp_iter` function, and that
Iterator types should also define the :c:member:`~PyTypeObject.tp_iter` function, and that
function should return the iterator instance itself (not a new iterator
instance).
@ -675,7 +675,7 @@ type objects) *must* have the :attr:`ob_size` field.
structures, declaring regular methods of this type.
For each entry in the array, an entry is added to the type's dictionary (see
:attr:`tp_dict` below) containing a method descriptor.
:c:member:`~PyTypeObject.tp_dict` below) containing a method descriptor.
This field is not inherited by subtypes (methods are inherited through a
different mechanism).
@ -688,7 +688,7 @@ type objects) *must* have the :attr:`ob_size` field.
this type.
For each entry in the array, an entry is added to the type's dictionary (see
:attr:`tp_dict` below) containing a member descriptor.
:c:member:`~PyTypeObject.tp_dict` below) containing a member descriptor.
This field is not inherited by subtypes (members are inherited through a
different mechanism).
@ -700,7 +700,7 @@ type objects) *must* have the :attr:`ob_size` field.
structures, declaring computed attributes of instances of this type.
For each entry in the array, an entry is added to the type's dictionary (see
:attr:`tp_dict` below) containing a getset descriptor.
:c:member:`~PyTypeObject.tp_dict` below) containing a getset descriptor.
This field is not inherited by subtypes (computed attributes are inherited
through a different mechanism).
@ -748,7 +748,7 @@ type objects) *must* have the :attr:`ob_size` field.
.. warning::
It is not safe to use :c:func:`PyDict_SetItem` on or otherwise modify
:attr:`tp_dict` with the dictionary C-API.
:c:member:`~PyTypeObject.tp_dict` with the dictionary C-API.
.. c:member:: descrgetfunc PyTypeObject.tp_descr_get
@ -784,7 +784,7 @@ type objects) *must* have the :attr:`ob_size` field.
the instance variable dictionary; this offset is used by
:c:func:`PyObject_GenericGetAttr`.
Do not confuse this field with :attr:`tp_dict`; that is the dictionary for
Do not confuse this field with :c:member:`~PyTypeObject.tp_dict`; that is the dictionary for
attributes of the type object itself.
If the value of this field is greater than zero, it specifies the offset from
@ -793,20 +793,20 @@ type objects) *must* have the :attr:`ob_size` field.
offset is more expensive to use, and should only be used when the instance
structure contains a variable-length part. This is used for example to add an
instance variable dictionary to subtypes of :class:`str` or :class:`tuple`. Note
that the :attr:`tp_basicsize` field should account for the dictionary added to
that the :c:member:`~PyTypeObject.tp_basicsize` field should account for the dictionary added to
the end in that case, even though the dictionary is not included in the basic
object layout. On a system with a pointer size of 4 bytes,
:attr:`tp_dictoffset` should be set to ``-4`` to indicate that the dictionary is
:c:member:`~PyTypeObject.tp_dictoffset` should be set to ``-4`` to indicate that the dictionary is
at the very end of the structure.
The real dictionary offset in an instance can be computed from a negative
:attr:`tp_dictoffset` as follows::
:c:member:`~PyTypeObject.tp_dictoffset` as follows::
dictoffset = tp_basicsize + abs(ob_size)*tp_itemsize + tp_dictoffset
if dictoffset is not aligned on sizeof(void*):
round up to sizeof(void*)
where :attr:`tp_basicsize`, :attr:`tp_itemsize` and :attr:`tp_dictoffset` are
where :c:member:`~PyTypeObject.tp_basicsize`, :c:member:`~PyTypeObject.tp_itemsize` and :c:member:`~PyTypeObject.tp_dictoffset` are
taken from the type object, and :attr:`ob_size` is taken from the instance. The
absolute value is taken because ints use the sign of :attr:`ob_size` to
store the sign of the number. (There's never a need to do this calculation
@ -815,15 +815,15 @@ type objects) *must* have the :attr:`ob_size` field.
This field is inherited by subtypes, but see the rules listed below. A subtype
may override this offset; this means that the subtype instances store the
dictionary at a difference offset than the base type. Since the dictionary is
always found via :attr:`tp_dictoffset`, this should not be a problem.
always found via :c:member:`~PyTypeObject.tp_dictoffset`, this should not be a problem.
When a type defined by a class statement has no :attr:`__slots__` declaration,
and none of its base types has an instance variable dictionary, a dictionary
slot is added to the instance layout and the :attr:`tp_dictoffset` is set to
slot is added to the instance layout and the :c:member:`~PyTypeObject.tp_dictoffset` is set to
that slot's offset.
When a type defined by a class statement has a :attr:`__slots__` declaration,
the type inherits its :attr:`tp_dictoffset` from its base type.
the type inherits its :c:member:`~PyTypeObject.tp_dictoffset` from its base type.
(Adding a slot named :attr:`__dict__` to the :attr:`__slots__` declaration does
not have the expected effect, it just causes confusion. Maybe this should be
@ -847,12 +847,12 @@ type objects) *must* have the :attr:`ob_size` field.
arguments represent positional and keyword arguments of the call to
:meth:`__init__`.
The :attr:`tp_init` function, if not *NULL*, is called when an instance is
created normally by calling its type, after the type's :attr:`tp_new` function
has returned an instance of the type. If the :attr:`tp_new` function returns an
The :c:member:`~PyTypeObject.tp_init` function, if not *NULL*, is called when an instance is
created normally by calling its type, after the type's :c:member:`~PyTypeObject.tp_new` function
has returned an instance of the type. If the :c:member:`~PyTypeObject.tp_new` function returns an
instance of some other type that is not a subtype of the original type, no
:attr:`tp_init` function is called; if :attr:`tp_new` returns an instance of a
subtype of the original type, the subtype's :attr:`tp_init` is called.
:c:member:`~PyTypeObject.tp_init` function is called; if :c:member:`~PyTypeObject.tp_new` returns an instance of a
subtype of the original type, the subtype's :c:member:`~PyTypeObject.tp_init` is called.
This field is inherited by subtypes.
@ -869,14 +869,14 @@ type objects) *must* have the :attr:`ob_size` field.
initialization. It should return a pointer to a block of memory of adequate
length for the instance, suitably aligned, and initialized to zeros, but with
:attr:`ob_refcnt` set to ``1`` and :attr:`ob_type` set to the type argument. If
the type's :attr:`tp_itemsize` is non-zero, the object's :attr:`ob_size` field
the type's :c:member:`~PyTypeObject.tp_itemsize` is non-zero, the object's :attr:`ob_size` field
should be initialized to *nitems* and the length of the allocated memory block
should be ``tp_basicsize + nitems*tp_itemsize``, rounded up to a multiple of
``sizeof(void*)``; otherwise, *nitems* is not used and the length of the block
should be :attr:`tp_basicsize`.
should be :c:member:`~PyTypeObject.tp_basicsize`.
Do not use this function to do any other instance initialization, not even to
allocate additional memory; that should be done by :attr:`tp_new`.
allocate additional memory; that should be done by :c:member:`~PyTypeObject.tp_new`.
This field is inherited by static subtypes, but not by dynamic subtypes
(subtypes created by a class statement); in the latter, this field is always set
@ -898,20 +898,20 @@ type objects) *must* have the :attr:`ob_size` field.
The subtype argument is the type of the object being created; the *args* and
*kwds* arguments represent positional and keyword arguments of the call to the
type. Note that subtype doesn't have to equal the type whose :attr:`tp_new`
type. Note that subtype doesn't have to equal the type whose :c:member:`~PyTypeObject.tp_new`
function is called; it may be a subtype of that type (but not an unrelated
type).
The :attr:`tp_new` function should call ``subtype->tp_alloc(subtype, nitems)``
The :c:member:`~PyTypeObject.tp_new` function should call ``subtype->tp_alloc(subtype, nitems)``
to allocate space for the object, and then do only as much further
initialization as is absolutely necessary. Initialization that can safely be
ignored or repeated should be placed in the :attr:`tp_init` handler. A good
ignored or repeated should be placed in the :c:member:`~PyTypeObject.tp_init` handler. A good
rule of thumb is that for immutable types, all initialization should take place
in :attr:`tp_new`, while for mutable types, most initialization should be
deferred to :attr:`tp_init`.
in :c:member:`~PyTypeObject.tp_new`, while for mutable types, most initialization should be
deferred to :c:member:`~PyTypeObject.tp_init`.
This field is inherited by subtypes, except it is not inherited by static types
whose :attr:`tp_base` is *NULL* or ``&PyBaseObject_Type``.
whose :c:member:`~PyTypeObject.tp_base` is *NULL* or ``&PyBaseObject_Type``.
.. c:member:: destructor PyTypeObject.tp_free
@ -935,7 +935,7 @@ type objects) *must* have the :attr:`ob_size` field.
The garbage collector needs to know whether a particular object is collectible
or not. Normally, it is sufficient to look at the object's type's
:attr:`tp_flags` field, and check the :const:`Py_TPFLAGS_HAVE_GC` flag bit. But
:c:member:`~PyTypeObject.tp_flags` field, and check the :const:`Py_TPFLAGS_HAVE_GC` flag bit. But
some types have a mixture of statically and dynamically allocated instances, and
the statically allocated instances are not collectible. Such types should
define this function; it should return ``1`` for a collectible instance, and
@ -1006,7 +1006,7 @@ subtypes.
.. c:member:: PyTypeObject* PyTypeObject.tp_next
Pointer to the next type object with a non-zero :attr:`tp_allocs` field.
Pointer to the next type object with a non-zero :c:member:`~PyTypeObject.tp_allocs` field.
Also, note that, in a garbage collected Python, tp_dealloc may be called from
any Python thread, not just the thread which created the object (if the object
@ -1145,13 +1145,13 @@ Sequence Object Structures
This function is used by :c:func:`PySequence_Concat` and has the same
signature. It is also used by the ``+`` operator, after trying the numeric
addition via the :attr:`tp_as_number.nb_add` slot.
addition via the :c:member:`~PyTypeObject.tp_as_number.nb_add` slot.
.. c:member:: ssizeargfunc PySequenceMethods.sq_repeat
This function is used by :c:func:`PySequence_Repeat` and has the same
signature. It is also used by the ``*`` operator, after trying numeric
multiplication via the :attr:`tp_as_number.nb_mul` slot.
multiplication via the :c:member:`~PyTypeObject.tp_as_number.nb_mul` slot.
.. c:member:: ssizeargfunc PySequenceMethods.sq_item