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[3.14] gh-144473: Add "steal" term to glossary; clarify "stealing" on error (GH-144502) (GH-152772)
With one exception, all "stealing" functions also steal on error, but it makes sense to note this in each case. (cherry picked from commit 34503f3) Co-authored-by: Peter Bierma <zintensitydev@gmail.com>
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Doc/c-api/bytes.rst

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@@ -180,10 +180,11 @@ called with a non-bytes parameter.
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.. c:function:: void PyBytes_Concat(PyObject **bytes, PyObject *newpart)
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Create a new bytes object in *\*bytes* containing the contents of *newpart*
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appended to *bytes*; the caller will own the new reference. The reference to
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the old value of *bytes* will be stolen. If the new object cannot be
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created, the old reference to *bytes* will still be discarded and the value
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of *\*bytes* will be set to ``NULL``; the appropriate exception will be set.
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appended to *bytes*; the caller will own the new reference.
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The reference to the old value of *bytes* will be ":term:`stolen <steal>`".
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If the new object cannot be created, the old reference to *bytes* will still
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be "stolen", the value of *\*bytes* will be set to ``NULL``, and
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the appropriate exception will be set.
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.. note::
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If *newpart* implements the buffer protocol, then the buffer

Doc/c-api/dict.rst

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@@ -89,8 +89,8 @@ Dictionary Objects
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Insert *val* into the dictionary *p* with a key of *key*. *key* must be
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:term:`hashable`; if it isn't, :exc:`TypeError` will be raised. Return
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``0`` on success or ``-1`` on failure. This function *does not* steal a
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reference to *val*.
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``0`` on success or ``-1`` on failure.
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This function *does not* ":term:`steal`" a reference to *val*.
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.. note::
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Doc/c-api/exceptions.rst

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@@ -503,7 +503,8 @@ Querying the error indicator
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.. warning::
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This call steals a reference to *exc*, which must be a valid exception.
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This call ":term:`steals <steal>`" a reference to *exc*,
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which must be a valid exception.
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.. versionadded:: 3.12
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@@ -641,7 +642,8 @@ Querying the error indicator
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Set the exception info, as known from ``sys.exc_info()``. This refers
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to an exception that was *already caught*, not to an exception that was
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freshly raised. This function steals the references of the arguments.
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freshly raised. This function ":term:`steals <steal>`" the references
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of the arguments.
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To clear the exception state, pass ``NULL`` for all three arguments.
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This function is kept for backwards compatibility. Prefer using
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:c:func:`PyErr_SetHandledException`.
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.. versionchanged:: 3.11
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The ``type`` and ``traceback`` arguments are no longer used and
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can be NULL. The interpreter now derives them from the exception
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instance (the ``value`` argument). The function still steals
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references of all three arguments.
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instance (the ``value`` argument). The function still
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":term:`steals <steal>`" references of all three arguments.
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Signal Handling
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Set the context associated with the exception to *ctx*. Use ``NULL`` to clear
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it. There is no type check to make sure that *ctx* is an exception instance.
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This steals a reference to *ctx*.
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This ":term:`steals <steal>`" a reference to *ctx*.
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.. c:function:: PyObject* PyException_GetCause(PyObject *ex)
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Set the cause associated with the exception to *cause*. Use ``NULL`` to clear
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it. There is no type check to make sure that *cause* is either an exception
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instance or ``None``. This steals a reference to *cause*.
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instance or ``None``.
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This ":term:`steals <steal>`" a reference to *cause*.
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The :attr:`~BaseException.__suppress_context__` attribute is implicitly set
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to ``True`` by this function.

Doc/c-api/gen.rst

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@@ -35,15 +35,15 @@ than explicitly calling :c:func:`PyGen_New` or :c:func:`PyGen_NewWithQualName`.
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.. c:function:: PyObject* PyGen_New(PyFrameObject *frame)
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Create and return a new generator object based on the *frame* object.
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A reference to *frame* is stolen by this function. The argument must not be
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``NULL``.
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A reference to *frame* is ":term:`stolen <steal>`" by this function (even
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on error). The argument must not be ``NULL``.
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.. c:function:: PyObject* PyGen_NewWithQualName(PyFrameObject *frame, PyObject *name, PyObject *qualname)
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Create and return a new generator object based on the *frame* object,
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with ``__name__`` and ``__qualname__`` set to *name* and *qualname*.
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A reference to *frame* is stolen by this function. The *frame* argument
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must not be ``NULL``.
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A reference to *frame* is ":term:`stolen <steal>`" by this function (even
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on error). The *frame* argument must not be ``NULL``.
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.. c:function:: PyCodeObject* PyGen_GetCode(PyGenObject *gen)
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.. c:function:: PyObject *PyAsyncGen_New(PyFrameObject *frame, PyObject *name, PyObject *qualname)
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Create a new asynchronous generator wrapping *frame*, with ``__name__`` and
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``__qualname__`` set to *name* and *qualname*. *frame* is stolen by this
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function and must not be ``NULL``.
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``__qualname__`` set to *name* and *qualname*.
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*frame* is ":term:`stolen <steal>`" by this function (even on error) and
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must not be ``NULL``.
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On success, this function returns a :term:`strong reference` to the
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new asynchronous generator. On failure, this function returns ``NULL``

Doc/c-api/intro.rst

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@@ -641,9 +641,12 @@ the caller is said to *borrow* the reference. Nothing needs to be done for a
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Conversely, when a calling function passes in a reference to an object, there
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are two possibilities: the function *steals* a reference to the object, or it
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does not. *Stealing a reference* means that when you pass a reference to a
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function, that function assumes that it now owns that reference, and you are not
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responsible for it any longer.
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does not.
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*Stealing a reference* means that when you pass a reference to a
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function, that function assumes that it now owns that reference.
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Since the new owner can use :c:func:`!Py_DECREF` at its discretion,
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you (the caller) must not use that reference after the call.
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.. index::
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single: PyList_SetItem (C function)

Doc/c-api/list.rst

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@@ -102,8 +102,10 @@ List Objects
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.. note::
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This function "steals" a reference to *item* and discards a reference to
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an item already in the list at the affected position.
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This function ":term:`steals <steal>`" a reference to *item*,
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even on error.
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On success, it discards a reference to an item already in the list
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at the affected position (unless it was ``NULL``).
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.. c:function:: void PyList_SET_ITEM(PyObject *list, Py_ssize_t i, PyObject *o)
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.. note::
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This macro "steals" a reference to *item*, and, unlike
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This macro ":term:`steals <steal>`" a reference to *item*, and, unlike
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:c:func:`PyList_SetItem`, does *not* discard a reference to any item that
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is being replaced; any reference in *list* at position *i* will be
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leaked.

Doc/c-api/module.rst

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@@ -559,8 +559,8 @@ or code that creates modules dynamically.
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.. c:function:: int PyModule_Add(PyObject *module, const char *name, PyObject *value)
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Similar to :c:func:`PyModule_AddObjectRef`, but "steals" a reference
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to *value*.
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Similar to :c:func:`PyModule_AddObjectRef`, but ":term:`steals <steal>`"
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a reference to *value* (even on error).
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It can be called with a result of function that returns a new reference
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without bothering to check its result or even saving it to a variable.
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.. c:function:: int PyModule_AddObject(PyObject *module, const char *name, PyObject *value)
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Similar to :c:func:`PyModule_AddObjectRef`, but steals a reference to
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*value* on success (if it returns ``0``).
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Similar to :c:func:`PyModule_AddObjectRef`, but :term:`steals <steal>`
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a reference to *value* on success (if it returns ``0``).
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The new :c:func:`PyModule_Add` or :c:func:`PyModule_AddObjectRef`
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functions are recommended, since it is

Doc/c-api/sequence.rst

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Assign object *v* to the *i*\ th element of *o*. Raise an exception
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and return ``-1`` on failure; return ``0`` on success. This
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is the equivalent of the Python statement ``o[i] = v``. This function *does
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not* steal a reference to *v*.
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not* ":term:`steal`" a reference to *v*.
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If *v* is ``NULL``, the element is deleted, but this feature is
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deprecated in favour of using :c:func:`PySequence_DelItem`.

Doc/c-api/threads.rst

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@@ -741,7 +741,7 @@ pointer and a void pointer argument.
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Asynchronously raise an exception in a thread. The *id* argument is the thread
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id of the target thread; *exc* is the exception object to be raised. This
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function does not steal any references to *exc*. To prevent naive misuse, you
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function does not :term:`steal` any references to *exc*. To prevent naive misuse, you
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must write your own C extension to call this. Must be called with an :term:`attached thread state`.
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Returns the number of thread states modified; this is normally one, but will be
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zero if the thread id isn't found. If *exc* is ``NULL``, the pending

Doc/c-api/tuple.rst

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.. note::
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This function "steals" a reference to *o* and discards a reference to
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an item already in the tuple at the affected position.
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This function ":term:`steals <steal>`" a reference to *o* and discards
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a reference to an item already in the tuple at the affected position
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(unless it was NULL).
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.. c:function:: void PyTuple_SET_ITEM(PyObject *p, Py_ssize_t pos, PyObject *o)
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.. note::
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This function "steals" a reference to *o*, and, unlike
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This function ":term:`steals <steal>`" a reference to *o*, and, unlike
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:c:func:`PyTuple_SetItem`, does *not* discard a reference to any item that
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is being replaced; any reference in the tuple at position *pos* will be
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.. note::
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This function "steals" a reference to *o*.
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This function ":term:`steals <steal>`" a reference to *o*.
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.. c:function:: void PyStructSequence_SET_ITEM(PyObject *p, Py_ssize_t *pos, PyObject *o)

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