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<!DOCTYPE html>

<head>

<title>Parsing arguments and building values — مستندات Python3.14.6</title><meta name="viewport" content="width=device-width, initial-scale=1.0">

title="جستجو در مستندات Python3.14.6"

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<h3><a href="../contents.html">فهرست عناوین</a></h3>

<ul>

<li><a class="reference internal" href="#">Parsing arguments and building values</a><ul>

<li><a class="reference internal" href="#parsing-arguments">Parsing arguments</a><ul>

<li><a class="reference internal" href="#strings-and-buffers">Strings and buffers</a></li>

<li><a class="reference internal" href="#numbers">Numbers</a></li>

<li><a class="reference internal" href="#other-objects">Other objects</a></li>

<li><a class="reference internal" href="#api-functions">API Functions</a></li>

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<li><a class="reference internal" href="#building-values">Building values</a></li>

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<h1>Parsing arguments and building values<a class="headerlink" href="#parsing-arguments-and-building-values" title="Link to this heading">¶</a></h1>

These functions are useful when creating your own extension functions and

methods. Additional information and examples are available in

<a class="reference internal" href="../extending/index.html#extending-index">Extending and Embedding the Python Interpreter</a>.

The first three of these functions described, <a class="reference internal" href="#c.PyArg_ParseTuple" title="PyArg_ParseTuple"><code class="xref c c-func docutils literal notranslate">PyArg_ParseTuple()</code></a>,

<a class="reference internal" href="#c.PyArg_ParseTupleAndKeywords" title="PyArg_ParseTupleAndKeywords"><code class="xref c c-func docutils literal notranslate">PyArg_ParseTupleAndKeywords()</code></a>, and <a class="reference internal" href="#c.PyArg_Parse" title="PyArg_Parse"><code class="xref c c-func docutils literal notranslate">PyArg_Parse()</code></a>, all use format

strings which are used to tell the function about the expected arguments. The

format strings use the same syntax for each of these functions.

<h2>Parsing arguments<a class="headerlink" href="#parsing-arguments" title="Link to this heading">¶</a></h2>

A format string consists of zero or more "format units." A format unit

describes one Python object; it is usually a single character or a parenthesized

sequence of format units. With a few exceptions, a format unit that is not a

parenthesized sequence normally corresponds to a single address argument to

these functions. In the following description, the quoted form is the format

unit; the entry in (round) parentheses is the Python object type that matches

the format unit; and the entry in [square] brackets is the type of the C

variable(s) whose address should be passed.

<h3>Strings and buffers<a class="headerlink" href="#strings-and-buffers" title="Link to this heading">¶</a></h3>

توجه

On Python 3.12 and older, the macro <code class="xref c c-macro docutils literal notranslate">PY_SSIZE_T_CLEAN</code> must be

defined before including <code class="file docutils literal notranslate">Python.h</code> to use all <code class="docutils literal notranslate">#</code> variants of

formats (<code class="docutils literal notranslate">s#</code>, <code class="docutils literal notranslate">y#</code>, etc.) explained below.

This is not necessary on Python 3.13 and later.

</div>

These formats allow accessing an object as a contiguous chunk of memory.

You don't have to provide raw storage for the returned unicode or bytes

area.

Unless otherwise stated, buffers are not NUL-terminated.

There are three ways strings and buffers can be converted to C:

<ul>

<li>Formats such as <code class="docutils literal notranslate">y*</code> and <code class="docutils literal notranslate">s*</code> fill a <a class="reference internal" href="buffer.html#c.Py_buffer" title="Py_buffer"><code class="xref c c-type docutils literal notranslate">Py_buffer</code></a> structure.

This locks the underlying buffer so that the caller can subsequently use

the buffer even inside a <a class="reference internal" href="threads.html#c.Py_BEGIN_ALLOW_THREADS" title="Py_BEGIN_ALLOW_THREADS"><code class="xref c c-type docutils literal notranslate">Py_BEGIN_ALLOW_THREADS</code></a>

block without the risk of mutable data being resized or destroyed.

As a result, you have to call <a class="reference internal" href="buffer.html#c.PyBuffer_Release" title="PyBuffer_Release"><code class="xref c c-func docutils literal notranslate">PyBuffer_Release()</code></a> after you have

finished processing the data (or in any early abort case).</li>

<li>The <code class="docutils literal notranslate">es</code>, <code class="docutils literal notranslate">es#</code>, <code class="docutils literal notranslate">et</code> and <code class="docutils literal notranslate">et#</code> formats allocate the result buffer.

You have to call <a class="reference internal" href="memory.html#c.PyMem_Free" title="PyMem_Free"><code class="xref c c-func docutils literal notranslate">PyMem_Free()</code></a> after you have finished

processing the data (or in any early abort case).</li>

<li>Other formats take a <a class="reference internal" href="../library/stdtypes.html#str" title="str"><code class="xref py py-class docutils literal notranslate">str</code></a> or a read-only <a class="reference internal" href="../glossary.html#term-bytes-like-object">bytes-like object</a>,

such as <a class="reference internal" href="../library/stdtypes.html#bytes" title="bytes"><code class="xref py py-class docutils literal notranslate">bytes</code></a>, and provide a <code class="docutils literal notranslate">const char *</code> pointer to

its buffer.

In this case the buffer is "borrowed": it is managed by the corresponding

Python object, and shares the lifetime of this object.

You won't have to release any memory yourself.

To ensure that the underlying buffer may be safely borrowed, the object's

<a class="reference internal" href="typeobj.html#c.PyBufferProcs.bf_releasebuffer" title="PyBufferProcs.bf_releasebuffer"><code class="xref c c-member docutils literal notranslate">PyBufferProcs.bf_releasebuffer</code></a> field must be <code class="docutils literal notranslate">NULL</code>.

This disallows common mutable objects such as <a class="reference internal" href="../library/stdtypes.html#bytearray" title="bytearray"><code class="xref py py-class docutils literal notranslate">bytearray</code></a>,

but also some read-only objects such as <a class="reference internal" href="../library/stdtypes.html#memoryview" title="memoryview"><code class="xref py py-class docutils literal notranslate">memoryview</code></a> of

<a class="reference internal" href="../library/stdtypes.html#bytes" title="bytes"><code class="xref py py-class docutils literal notranslate">bytes</code></a>.

Besides this <code class="docutils literal notranslate">bf_releasebuffer</code> requirement, there is no check to verify

whether the input object is immutable (e.g. whether it would honor a request

for a writable buffer, or whether another thread can mutate the data).

</li>

</ul>

<dl>

A pointer to an existing string is stored in the character pointer

variable whose address you pass. The C string is NUL-terminated.

The Python string must not contain embedded null code points; if it does,

a <a class="reference internal" href="../library/exceptions.html#ValueError" title="ValueError"><code class="xref py py-exc docutils literal notranslate">ValueError</code></a> exception is raised. Unicode objects are converted

to C strings using <code class="docutils literal notranslate">'utf-8'</code> encoding. If this conversion fails, a

<a class="reference internal" href="../library/exceptions.html#UnicodeError" title="UnicodeError"><code class="xref py py-exc docutils literal notranslate">UnicodeError</code></a> is raised.

توجه

This format does not accept <a class="reference internal" href="../glossary.html#term-bytes-like-object">bytes-like objects</a>. If you want to accept

filesystem paths and convert them to C character strings, it is

preferable to use the <code class="docutils literal notranslate">O&</code> format with <a class="reference internal" href="unicode.html#c.PyUnicode_FSConverter" title="PyUnicode_FSConverter"><code class="xref c c-func docutils literal notranslate">PyUnicode_FSConverter()</code></a>

as converter.

</div>

تغییر داده شده در نسخه 3.5: Previously, <a class="reference internal" href="../library/exceptions.html#TypeError" title="TypeError"><code class="xref py py-exc docutils literal notranslate">TypeError</code></a> was raised when embedded null code points

were encountered in the Python string.

</div>

</dd>

<dt><code class="docutils literal notranslate">s*</code> (<a class="reference internal" href="../library/stdtypes.html#str" title="str"><code class="xref py py-class docutils literal notranslate">str</code></a> or <a class="reference internal" href="../glossary.html#term-bytes-like-object">bytes-like object</a>) [Py_buffer]</dt><dd>This format accepts Unicode objects as well as bytes-like objects.

It fills a <a class="reference internal" href="buffer.html#c.Py_buffer" title="Py_buffer"><code class="xref c c-type docutils literal notranslate">Py_buffer</code></a> structure provided by the caller.

In this case the resulting C string may contain embedded NUL bytes.

Unicode objects are converted to C strings using <code class="docutils literal notranslate">'utf-8'</code> encoding.

</dd>

<dt><code class="docutils literal notranslate">s#</code> (<a class="reference internal" href="../library/stdtypes.html#str" title="str"><code class="xref py py-class docutils literal notranslate">str</code></a>, read-only <a class="reference internal" href="../glossary.html#term-bytes-like-object">bytes-like object</a>) [const char *, <a class="reference internal" href="intro.html#c.Py_ssize_t" title="Py_ssize_t"><code class="xref c c-type docutils literal notranslate">Py_ssize_t</code></a>]</dt><dd>Like <code class="docutils literal notranslate">s*</code>, except that it provides a <a class="reference internal" href="#c-arg-borrowed-buffer">borrowed buffer</a>.

The result is stored into two C variables,

the first one a pointer to a C string, the second one its length.

The string may contain embedded null bytes. Unicode objects are converted

to C strings using <code class="docutils literal notranslate">'utf-8'</code> encoding.

</dd>

<dt><code class="docutils literal notranslate">z</code> (<a class="reference internal" href="../library/stdtypes.html#str" title="str"><code class="xref py py-class docutils literal notranslate">str</code></a> or <code class="docutils literal notranslate">None</code>) [const char *]</dt><dd>Like <code class="docutils literal notranslate">s</code>, but the Python object may also be <code class="docutils literal notranslate">None</code>, in which case the C

pointer is set to <code class="docutils literal notranslate">NULL</code>.

</dd>

<dt><code class="docutils literal notranslate">z*</code> (<a class="reference internal" href="../library/stdtypes.html#str" title="str"><code class="xref py py-class docutils literal notranslate">str</code></a>, <a class="reference internal" href="../glossary.html#term-bytes-like-object">bytes-like object</a> or <code class="docutils literal notranslate">None</code>) [Py_buffer]</dt><dd>Like <code class="docutils literal notranslate">s*</code>, but the Python object may also be <code class="docutils literal notranslate">None</code>, in which case the

<code class="docutils literal notranslate">buf</code> member of the <a class="reference internal" href="buffer.html#c.Py_buffer" title="Py_buffer"><code class="xref c c-type docutils literal notranslate">Py_buffer</code></a> structure is set to <code class="docutils literal notranslate">NULL</code>.

</dd>

<dt><code class="docutils literal notranslate">z#</code> (<a class="reference internal" href="../library/stdtypes.html#str" title="str"><code class="xref py py-class docutils literal notranslate">str</code></a>, read-only <a class="reference internal" href="../glossary.html#term-bytes-like-object">bytes-like object</a> or <code class="docutils literal notranslate">None</code>) [const char *, <a class="reference internal" href="intro.html#c.Py_ssize_t" title="Py_ssize_t"><code class="xref c c-type docutils literal notranslate">Py_ssize_t</code></a>]</dt><dd>Like <code class="docutils literal notranslate">s#</code>, but the Python object may also be <code class="docutils literal notranslate">None</code>, in which case the C

pointer is set to <code class="docutils literal notranslate">NULL</code>.

</dd>

<dt><code class="docutils literal notranslate">y</code> (read-only <a class="reference internal" href="../glossary.html#term-bytes-like-object">bytes-like object</a>) [const char *]</dt><dd>This format converts a bytes-like object to a C pointer to a

<a class="reference internal" href="#c-arg-borrowed-buffer">borrowed</a> character string;

it does not accept Unicode objects. The bytes buffer must not

contain embedded null bytes; if it does, a <a class="reference internal" href="../library/exceptions.html#ValueError" title="ValueError"><code class="xref py py-exc docutils literal notranslate">ValueError</code></a>

exception is raised.

encountered in the bytes buffer.

</div>

</dd>

<dt><code class="docutils literal notranslate">y*</code> (<a class="reference internal" href="../glossary.html#term-bytes-like-object">bytes-like object</a>) [Py_buffer]</dt><dd>This variant on <code class="docutils literal notranslate">s*</code> doesn't accept Unicode objects, only

bytes-like objects. This is the recommended way to accept

binary data.

</dd>

<dt><code class="docutils literal notranslate">y#</code> (read-only <a class="reference internal" href="../glossary.html#term-bytes-like-object">bytes-like object</a>) [const char *, <a class="reference internal" href="intro.html#c.Py_ssize_t" title="Py_ssize_t"><code class="xref c c-type docutils literal notranslate">Py_ssize_t</code></a>]</dt><dd>This variant on <code class="docutils literal notranslate">s#</code> doesn't accept Unicode objects, only bytes-like

objects.

</dd>

<dt><code class="docutils literal notranslate">S</code> (<a class="reference internal" href="../library/stdtypes.html#bytes" title="bytes"><code class="xref py py-class docutils literal notranslate">bytes</code></a>) [PyBytesObject *]</dt><dd>Requires that the Python object is a <a class="reference internal" href="../library/stdtypes.html#bytes" title="bytes"><code class="xref py py-class docutils literal notranslate">bytes</code></a> object, without

attempting any conversion. Raises <a class="reference internal" href="../library/exceptions.html#TypeError" title="TypeError"><code class="xref py py-exc docutils literal notranslate">TypeError</code></a> if the object is not

a bytes object. The C variable may also be declared as <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>*.

</dd>

<dt><code class="docutils literal notranslate">Y</code> (<a class="reference internal" href="../library/stdtypes.html#bytearray" title="bytearray"><code class="xref py py-class docutils literal notranslate">bytearray</code></a>) [PyByteArrayObject *]</dt><dd>Requires that the Python object is a <a class="reference internal" href="../library/stdtypes.html#bytearray" title="bytearray"><code class="xref py py-class docutils literal notranslate">bytearray</code></a> object, without

a <code class="xref py py-class docutils literal notranslate">bytearray</code> object. The C variable may also be declared as <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>*.

</dd>

<dt><code class="docutils literal notranslate">U</code> (<a class="reference internal" href="../library/stdtypes.html#str" title="str"><code class="xref py py-class docutils literal notranslate">str</code></a>) [PyObject *]</dt><dd>Requires that the Python object is a Unicode object, without attempting

any conversion. Raises <a class="reference internal" href="../library/exceptions.html#TypeError" title="TypeError"><code class="xref py py-exc docutils literal notranslate">TypeError</code></a> if the object is not a Unicode

object. The C variable may also be declared as <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>*.

</dd>

<dt><code class="docutils literal notranslate">w*</code> (read-write <a class="reference internal" href="../glossary.html#term-bytes-like-object">bytes-like object</a>) [Py_buffer]</dt><dd>This format accepts any object which implements the read-write buffer

interface. It fills a <a class="reference internal" href="buffer.html#c.Py_buffer" title="Py_buffer"><code class="xref c c-type docutils literal notranslate">Py_buffer</code></a> structure provided by the caller.

The buffer may contain embedded null bytes. The caller has to call

<a class="reference internal" href="buffer.html#c.PyBuffer_Release" title="PyBuffer_Release"><code class="xref c c-func docutils literal notranslate">PyBuffer_Release()</code></a> when it is done with the buffer.

</dd>

<dt><code class="docutils literal notranslate">es</code> (<a class="reference internal" href="../library/stdtypes.html#str" title="str"><code class="xref py py-class docutils literal notranslate">str</code></a>) [const char *encoding, char **buffer]</dt><dd>This variant on <code class="docutils literal notranslate">s</code> is used for encoding Unicode into a character buffer.

It only works for encoded data without embedded NUL bytes.

This format requires two arguments. The first is only used as input, and

must be a const char* which points to the name of an encoding as a

NUL-terminated string, or <code class="docutils literal notranslate">NULL</code>, in which case <code class="docutils literal notranslate">'utf-8'</code> encoding is used.

An exception is raised if the named encoding is not known to Python. The

second argument must be a char**; the value of the pointer it

references will be set to a buffer with the contents of the argument text.

The text will be encoded in the encoding specified by the first argument.

<a class="reference internal" href="#c.PyArg_ParseTuple" title="PyArg_ParseTuple"><code class="xref c c-func docutils literal notranslate">PyArg_ParseTuple()</code></a> will allocate a buffer of the needed size, copy the

encoded data into this buffer and adjust *buffer to reference the newly

allocated storage. The caller is responsible for calling <a class="reference internal" href="memory.html#c.PyMem_Free" title="PyMem_Free"><code class="xref c c-func docutils literal notranslate">PyMem_Free()</code></a> to

free the allocated buffer after use.

</dd>

<dt><code class="docutils literal notranslate">et</code> (<a class="reference internal" href="../library/stdtypes.html#str" title="str"><code class="xref py py-class docutils literal notranslate">str</code></a>, <a class="reference internal" href="../library/stdtypes.html#bytes" title="bytes"><code class="xref py py-class docutils literal notranslate">bytes</code></a> or <a class="reference internal" href="../library/stdtypes.html#bytearray" title="bytearray"><code class="xref py py-class docutils literal notranslate">bytearray</code></a>) [const char *encoding, char **buffer]</dt><dd>Same as <code class="docutils literal notranslate">es</code> except that byte string objects are passed through without

recoding them. Instead, the implementation assumes that the byte string object uses

the encoding passed in as parameter.

</dd>

<dt><code class="docutils literal notranslate">es#</code> (<a class="reference internal" href="../library/stdtypes.html#str" title="str"><code class="xref py py-class docutils literal notranslate">str</code></a>) [const char *encoding, char **buffer, <a class="reference internal" href="intro.html#c.Py_ssize_t" title="Py_ssize_t"><code class="xref c c-type docutils literal notranslate">Py_ssize_t</code></a> *buffer_length]</dt><dd>This variant on <code class="docutils literal notranslate">s#</code> is used for encoding Unicode into a character buffer.

Unlike the <code class="docutils literal notranslate">es</code> format, this variant allows input data which contains NUL

characters.

It requires three arguments. The first is only used as input, and must be a

const char* which points to the name of an encoding as a

An exception is raised if the named encoding is not known to Python. The

second argument must be a char**; the value of the pointer it

references will be set to a buffer with the contents of the argument text.

The text will be encoded in the encoding specified by the first argument.

The third argument must be a pointer to an integer; the referenced integer

will be set to the number of bytes in the output buffer.

There are two modes of operation:

If *buffer points a <code class="docutils literal notranslate">NULL</code> pointer, the function will allocate a buffer of

the needed size, copy the encoded data into this buffer and set *buffer to

reference the newly allocated storage. The caller is responsible for calling

<a class="reference internal" href="memory.html#c.PyMem_Free" title="PyMem_Free"><code class="xref c c-func docutils literal notranslate">PyMem_Free()</code></a> to free the allocated buffer after usage.

If *buffer points to a non-<code class="docutils literal notranslate">NULL</code> pointer (an already allocated buffer),

<a class="reference internal" href="#c.PyArg_ParseTuple" title="PyArg_ParseTuple"><code class="xref c c-func docutils literal notranslate">PyArg_ParseTuple()</code></a> will use this location as the buffer and interpret the

initial value of *buffer_length as the buffer size. It will then copy the

encoded data into the buffer and NUL-terminate it. If the buffer is not large

enough, a <a class="reference internal" href="../library/exceptions.html#ValueError" title="ValueError"><code class="xref py py-exc docutils literal notranslate">ValueError</code></a> will be set.

In both cases, *buffer_length is set to the length of the encoded data

without the trailing NUL byte.

</dd>

<dt><code class="docutils literal notranslate">et#</code> (<a class="reference internal" href="../library/stdtypes.html#str" title="str"><code class="xref py py-class docutils literal notranslate">str</code></a>, <a class="reference internal" href="../library/stdtypes.html#bytes" title="bytes"><code class="xref py py-class docutils literal notranslate">bytes</code></a> or <a class="reference internal" href="../library/stdtypes.html#bytearray" title="bytearray"><code class="xref py py-class docutils literal notranslate">bytearray</code></a>) [const char *encoding, char **buffer, <a class="reference internal" href="intro.html#c.Py_ssize_t" title="Py_ssize_t"><code class="xref c c-type docutils literal notranslate">Py_ssize_t</code></a> *buffer_length]</dt><dd>Same as <code class="docutils literal notranslate">es#</code> except that byte string objects are passed through without recoding

them. Instead, the implementation assumes that the byte string object uses the

encoding passed in as parameter.

</dd>

</dl>

تغییر داده شده در نسخه 3.12: <code class="docutils literal notranslate">u</code>, <code class="docutils literal notranslate">u#</code>, <code class="docutils literal notranslate">Z</code>, and <code class="docutils literal notranslate">Z#</code> are removed because they used a legacy

<code class="docutils literal notranslate">Py_UNICODE*</code> representation.

</div>

</section>

<h3>Numbers<a class="headerlink" href="#numbers" title="Link to this heading">¶</a></h3>

These formats allow representing Python numbers or single characters as C numbers.

Formats that require <a class="reference internal" href="../library/functions.html#int" title="int"><code class="xref py py-class docutils literal notranslate">int</code></a>, <a class="reference internal" href="../library/functions.html#float" title="float"><code class="xref py py-class docutils literal notranslate">float</code></a> or <a class="reference internal" href="../library/functions.html#complex" title="complex"><code class="xref py py-class docutils literal notranslate">complex</code></a> can

also use the corresponding special methods <a class="reference internal" href="../reference/datamodel.html#object.__index__" title="object.__index__"><code class="xref py py-meth docutils literal notranslate">__index__()</code></a>,

<a class="reference internal" href="../reference/datamodel.html#object.__float__" title="object.__float__"><code class="xref py py-meth docutils literal notranslate">__float__()</code></a> or <a class="reference internal" href="../reference/datamodel.html#object.__complex__" title="object.__complex__"><code class="xref py py-meth docutils literal notranslate">__complex__()</code></a> to convert

the Python object to the required type.

For signed integer formats, <a class="reference internal" href="../library/exceptions.html#OverflowError" title="OverflowError"><code class="xref py py-exc docutils literal notranslate">OverflowError</code></a> is raised if the value

is out of range for the C type.

For unsigned integer formats, no range checking is done --- the

most significant bits are silently truncated when the receiving field is too

small to receive the value.

<dl>

<dt><code class="docutils literal notranslate">b</code> (<a class="reference internal" href="../library/functions.html#int" title="int"><code class="xref py py-class docutils literal notranslate">int</code></a>) [unsigned char]</dt><dd>Convert a nonnegative Python integer to an unsigned tiny integer, stored in a C

unsigned char.

</dd>

<dt><code class="docutils literal notranslate">B</code> (<a class="reference internal" href="../library/functions.html#int" title="int"><code class="xref py py-class docutils literal notranslate">int</code></a>) [unsigned char]</dt><dd>Convert a Python integer to a tiny integer without overflow checking, stored in a C

unsigned char.

</dd>

<dt><code class="docutils literal notranslate">h</code> (<a class="reference internal" href="../library/functions.html#int" title="int"><code class="xref py py-class docutils literal notranslate">int</code></a>) [short int]</dt><dd>Convert a Python integer to a C short int.

</dd>

<dt><code class="docutils literal notranslate">H</code> (<a class="reference internal" href="../library/functions.html#int" title="int"><code class="xref py py-class docutils literal notranslate">int</code></a>) [unsigned short int]</dt><dd>Convert a Python integer to a C unsigned short int, without overflow

checking.

</dd>

<dt><code class="docutils literal notranslate">i</code> (<a class="reference internal" href="../library/functions.html#int" title="int"><code class="xref py py-class docutils literal notranslate">int</code></a>) [int]</dt><dd>Convert a Python integer to a plain C int.

</dd>

<dt><code class="docutils literal notranslate">I</code> (<a class="reference internal" href="../library/functions.html#int" title="int"><code class="xref py py-class docutils literal notranslate">int</code></a>) [unsigned int]</dt><dd>Convert a Python integer to a C unsigned int, without overflow

checking.

</dd>

<dt><code class="docutils literal notranslate">l</code> (<a class="reference internal" href="../library/functions.html#int" title="int"><code class="xref py py-class docutils literal notranslate">int</code></a>) [long int]</dt><dd>Convert a Python integer to a C long int.

</dd>

<dt><code class="docutils literal notranslate">k</code> (<a class="reference internal" href="../library/functions.html#int" title="int"><code class="xref py py-class docutils literal notranslate">int</code></a>) [unsigned long]</dt><dd>Convert a Python integer to a C unsigned long without

overflow checking.

تغییر داده شده در نسخه 3.14: Use <a class="reference internal" href="../reference/datamodel.html#object.__index__" title="object.__index__"><code class="xref py py-meth docutils literal notranslate">__index__()</code></a> if available.

</div>

</dd>

<dt><code class="docutils literal notranslate">L</code> (<a class="reference internal" href="../library/functions.html#int" title="int"><code class="xref py py-class docutils literal notranslate">int</code></a>) [long long]</dt><dd>Convert a Python integer to a C long long.

</dd>

<dt><code class="docutils literal notranslate">K</code> (<a class="reference internal" href="../library/functions.html#int" title="int"><code class="xref py py-class docutils literal notranslate">int</code></a>) [unsigned long long]</dt><dd>Convert a Python integer to a C unsigned long long

without overflow checking.

</div>

</dd>

<dt><code class="docutils literal notranslate">n</code> (<a class="reference internal" href="../library/functions.html#int" title="int"><code class="xref py py-class docutils literal notranslate">int</code></a>) [<a class="reference internal" href="intro.html#c.Py_ssize_t" title="Py_ssize_t"><code class="xref c c-type docutils literal notranslate">Py_ssize_t</code></a>]</dt><dd>Convert a Python integer to a C <a class="reference internal" href="intro.html#c.Py_ssize_t" title="Py_ssize_t"><code class="xref c c-type docutils literal notranslate">Py_ssize_t</code></a>.

</dd>

<dt><code class="docutils literal notranslate">c</code> (<a class="reference internal" href="../library/stdtypes.html#bytes" title="bytes"><code class="xref py py-class docutils literal notranslate">bytes</code></a> or <a class="reference internal" href="../library/stdtypes.html#bytearray" title="bytearray"><code class="xref py py-class docutils literal notranslate">bytearray</code></a> of length 1) [char]</dt><dd>Convert a Python byte, represented as a <a class="reference internal" href="../library/stdtypes.html#bytes" title="bytes"><code class="xref py py-class docutils literal notranslate">bytes</code></a> or

<a class="reference internal" href="../library/stdtypes.html#bytearray" title="bytearray"><code class="xref py py-class docutils literal notranslate">bytearray</code></a> object of length 1, to a C char.

تغییر داده شده در نسخه 3.3: Allow <a class="reference internal" href="../library/stdtypes.html#bytearray" title="bytearray"><code class="xref py py-class docutils literal notranslate">bytearray</code></a> objects.

</div>

</dd>

<dt><code class="docutils literal notranslate">C</code> (<a class="reference internal" href="../library/stdtypes.html#str" title="str"><code class="xref py py-class docutils literal notranslate">str</code></a> of length 1) [int]</dt><dd>Convert a Python character, represented as a <a class="reference internal" href="../library/stdtypes.html#str" title="str"><code class="xref py py-class docutils literal notranslate">str</code></a> object of

length 1, to a C int.

</dd>

<dt><code class="docutils literal notranslate">f</code> (<a class="reference internal" href="../library/functions.html#float" title="float"><code class="xref py py-class docutils literal notranslate">float</code></a>) [float]</dt><dd>Convert a Python floating-point number to a C float.

</dd>

<dt><code class="docutils literal notranslate">d</code> (<a class="reference internal" href="../library/functions.html#float" title="float"><code class="xref py py-class docutils literal notranslate">float</code></a>) [double]</dt><dd>Convert a Python floating-point number to a C double.

</dd>

<dt><code class="docutils literal notranslate">D</code> (<a class="reference internal" href="../library/functions.html#complex" title="complex"><code class="xref py py-class docutils literal notranslate">complex</code></a>) [Py_complex]</dt><dd>Convert a Python complex number to a C <a class="reference internal" href="complex.html#c.Py_complex" title="Py_complex"><code class="xref c c-type docutils literal notranslate">Py_complex</code></a> structure.

</dd>

</dl>

</section>

<h3>Other objects<a class="headerlink" href="#other-objects" title="Link to this heading">¶</a></h3>

<dt><code class="docutils literal notranslate">O</code> (object) [PyObject *]</dt><dd>Store a Python object (without any conversion) in a C object pointer. The C

program thus receives the actual object that was passed. A new

<a class="reference internal" href="../glossary.html#term-strong-reference">strong reference</a> to the object is not created

(i.e. its reference count is not increased).

The pointer stored is not <code class="docutils literal notranslate">NULL</code>.

</dd>

<dt><code class="docutils literal notranslate">O!</code> (object) [typeobject, PyObject *]</dt><dd>Store a Python object in a C object pointer. This is similar to <code class="docutils literal notranslate">O</code>, but

takes two C arguments: the first is the address of a Python type object, the

second is the address of the C variable (of type <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>*) into which

the object pointer is stored. If the Python object does not have the required

type, <a class="reference internal" href="../library/exceptions.html#TypeError" title="TypeError"><code class="xref py py-exc docutils literal notranslate">TypeError</code></a> is raised.

</dd>

</dl>

<dt><code class="docutils literal notranslate">O&</code> (object) [converter, address]</dt><dd>Convert a Python object to a C variable through a converter function. This

takes two arguments: the first is a function, the second is the address of a C

variable (of arbitrary type), converted to void*. The converter

function in turn is called as follows:

<div class="highlight-c notranslate"><div class="highlight"><pre>status = converter(object, address);

</pre></div>

</div>

where object is the Python object to be converted and address is the

void* argument that was passed to the <code class="docutils literal notranslate">PyArg_Parse*</code> function.

The returned status should be <code class="docutils literal notranslate">1</code> for a successful conversion and <code class="docutils literal notranslate">0</code> if

the conversion has failed. When the conversion fails, the converter function

should raise an exception and leave the content of address unmodified.

If the converter returns <code class="xref c c-macro docutils literal notranslate">Py_CLEANUP_SUPPORTED</code>, it may get called a

second time if the argument parsing eventually fails, giving the converter a

chance to release any memory that it had already allocated. In this second

call, the object parameter will be <code class="docutils literal notranslate">NULL</code>; address will have the same value

as in the original call.

Examples of converters: <a class="reference internal" href="unicode.html#c.PyUnicode_FSConverter" title="PyUnicode_FSConverter"><code class="xref c c-func docutils literal notranslate">PyUnicode_FSConverter()</code></a> and

<a class="reference internal" href="unicode.html#c.PyUnicode_FSDecoder" title="PyUnicode_FSDecoder"><code class="xref c c-func docutils literal notranslate">PyUnicode_FSDecoder()</code></a>.

تغییر داده شده در نسخه 3.1: <code class="xref c c-macro docutils literal notranslate">Py_CLEANUP_SUPPORTED</code> was added.

</div>

</dd>

the result to its equivalent C true/false integer value.

Sets the int to <code class="docutils literal notranslate">1</code> if the expression was true and <code class="docutils literal notranslate">0</code> if it was false.

This accepts any valid Python value. See <a class="reference internal" href="../library/stdtypes.html#truth">Truth Value Testing</a> for more

information about how Python tests values for truth.

Added in version 3.3.

</div>

</dd>

<dt><code class="docutils literal notranslate">(items)</code> (sequence) [matching-items]</dt><dd>The object must be a Python sequence (except <a class="reference internal" href="../library/stdtypes.html#str" title="str"><code class="xref py py-class docutils literal notranslate">str</code></a>, <a class="reference internal" href="../library/stdtypes.html#bytes" title="bytes"><code class="xref py py-class docutils literal notranslate">bytes</code></a>

or <a class="reference internal" href="../library/stdtypes.html#bytearray" title="bytearray"><code class="xref py py-class docutils literal notranslate">bytearray</code></a>) whose length is the number of format units

in items. The C arguments must correspond to the individual format units in

items. Format units for sequences may be nested.

If items contains format units which store a <a class="reference internal" href="#c-arg-borrowed-buffer">borrowed buffer</a> (<code class="docutils literal notranslate">s</code>, <code class="docutils literal notranslate">s#</code>, <code class="docutils literal notranslate">z</code>, <code class="docutils literal notranslate">z#</code>, <code class="docutils literal notranslate">y</code>, or <code class="docutils literal notranslate">y#</code>)

or a <a class="reference internal" href="../glossary.html#term-borrowed-reference">borrowed reference</a> (<code class="docutils literal notranslate">S</code>, <code class="docutils literal notranslate">Y</code>, <code class="docutils literal notranslate">U</code>, <code class="docutils literal notranslate">O</code>, or <code class="docutils literal notranslate">O!</code>),

the object must be a Python tuple.

The converter for the <code class="docutils literal notranslate">O&</code> format unit in items must not store

a borrowed buffer or a borrowed reference.

تغییر داده شده در نسخه 3.14: <a class="reference internal" href="../library/stdtypes.html#str" title="str"><code class="xref py py-class docutils literal notranslate">str</code></a> and <a class="reference internal" href="../library/stdtypes.html#bytearray" title="bytearray"><code class="xref py py-class docutils literal notranslate">bytearray</code></a> objects no longer accepted as a sequence.

</div>

منسوخ شده از نسخه 3.14: Non-tuple sequences are deprecated if items contains format units

which store a borrowed buffer or a borrowed reference.

</div>

</dd>

</dl>

A few other characters have a meaning in a format string. These may not occur

inside nested parentheses. They are:

<dl>

<dt><code class="docutils literal notranslate">|</code></dt><dd>Indicates that the remaining arguments in the Python argument list are optional.

The C variables corresponding to optional arguments should be initialized to

their default value --- when an optional argument is not specified,

variable(s).

</dd>

<dt><code class="docutils literal notranslate">$</code></dt><dd><a class="reference internal" href="#c.PyArg_ParseTupleAndKeywords" title="PyArg_ParseTupleAndKeywords"><code class="xref c c-func docutils literal notranslate">PyArg_ParseTupleAndKeywords()</code></a> only:

Indicates that the remaining arguments in the Python argument list are

keyword-only. Currently, all keyword-only arguments must also be optional

arguments, so <code class="docutils literal notranslate">|</code> must always be specified before <code class="docutils literal notranslate">$</code> in the format

string.

Added in version 3.3.

</div>

</dd>

<dt><code class="docutils literal notranslate">:</code></dt><dd>The list of format units ends here; the string after the colon is used as the

function name in error messages (the "associated value" of the exception that

</dd>

<dt><code class="docutils literal notranslate">;</code></dt><dd>The list of format units ends here; the string after the semicolon is used as

the error message instead of the default error message. <code class="docutils literal notranslate">:</code> and <code class="docutils literal notranslate">;</code>

mutually exclude each other.

</dd>

</dl>

Note that any Python object references which are provided to the caller are

borrowed references; do not release them

(i.e. do not decrement their reference count)!

Additional arguments passed to these functions must be addresses of variables

whose type is determined by the format string; these are used to store values

from the input tuple. There are a few cases, as described in the list of format

units above, where these parameters are used as input values; they should match

what is specified for the corresponding format unit in that case.

For the conversion to succeed, the arg object must match the format

and the format must be exhausted. On success, the

<code class="docutils literal notranslate">PyArg_Parse*</code> functions return true, otherwise they return

false and raise an appropriate exception. When the

<code class="docutils literal notranslate">PyArg_Parse*</code> functions fail due to conversion failure in one

of the format units, the variables at the addresses corresponding to that

and the following format units are left untouched.

</section>

<h3>API Functions<a class="headerlink" href="#api-functions" title="Link to this heading">¶</a></h3>

<dd> قسمتی از <a class="reference internal" href="stable.html#stable">ABI پایدار</a>.Parse the parameters of a function that takes only positional parameters into

local variables. Returns true on success; on failure, it returns false and

raises the appropriate exception.

</dd></dl>

int PyArg_VaParse(<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a> *args, const char *format, va_list vargs)<a class="headerlink" href="#c.PyArg_VaParse" title="Link to this definition">¶</a> </dt>

<dd> قسمتی از <a class="reference internal" href="stable.html#stable">ABI پایدار</a>.Identical to <a class="reference internal" href="#c.PyArg_ParseTuple" title="PyArg_ParseTuple"><code class="xref c c-func docutils literal notranslate">PyArg_ParseTuple()</code></a>, except that it accepts a va_list rather

than a variable number of arguments.

</dd></dl>

int PyArg_ParseTupleAndKeywords(<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a> *args, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a> *kw, const char *format, char *const *keywords, ...)<a class="headerlink" href="#c.PyArg_ParseTupleAndKeywords" title="Link to this definition">¶</a> </dt>

parameters into local variables.

The keywords argument is a <code class="docutils literal notranslate">NULL</code>-terminated array of keyword parameter

names specified as null-terminated ASCII or UTF-8 encoded C strings.

Empty names denote

<a class="reference internal" href="../glossary.html#positional-only-parameter">positional-only parameters</a>.

Returns true on success; on failure, it returns false and raises the

appropriate exception.

توجه

The keywords parameter declaration is char *const* in C and

This can be overridden with the <a class="reference internal" href="#c.PY_CXX_CONST" title="PY_CXX_CONST"><code class="xref c c-macro docutils literal notranslate">PY_CXX_CONST</code></a> macro.

</div>

تغییر داده شده در نسخه 3.6: Added support for <a class="reference internal" href="../glossary.html#positional-only-parameter">positional-only parameters</a>.

</div>

تغییر داده شده در نسخه 3.13: The keywords parameter has now type char *const* in C and

const char *const* in C++, instead of char**.

Added support for non-ASCII keyword parameter names.

</div>

</dd></dl>

int PyArg_VaParseTupleAndKeywords(<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a> *args, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a> *kw, const char *format, char *const *keywords, va_list vargs)<a class="headerlink" href="#c.PyArg_VaParseTupleAndKeywords" title="Link to this definition">¶</a> </dt>

<dd> قسمتی از <a class="reference internal" href="stable.html#stable">ABI پایدار</a>.Identical to <a class="reference internal" href="#c.PyArg_ParseTupleAndKeywords" title="PyArg_ParseTupleAndKeywords"><code class="xref c c-func docutils literal notranslate">PyArg_ParseTupleAndKeywords()</code></a>, except that it accepts a

va_list rather than a variable number of arguments.

</dd></dl>

int PyArg_ValidateKeywordArguments(<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>*)<a class="headerlink" href="#c.PyArg_ValidateKeywordArguments" title="Link to this definition">¶</a> </dt>

<dd> قسمتی از <a class="reference internal" href="stable.html#stable">ABI پایدار</a>.Ensure that the keys in the keywords argument dictionary are strings. This

is only needed if <a class="reference internal" href="#c.PyArg_ParseTupleAndKeywords" title="PyArg_ParseTupleAndKeywords"><code class="xref c c-func docutils literal notranslate">PyArg_ParseTupleAndKeywords()</code></a> is not used, since the

latter already does this check.

Added in version 3.2.

</div>

</dd></dl>

int PyArg_Parse(<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a> *args, const char *format, ...)<a class="headerlink" href="#c.PyArg_Parse" title="Link to this definition">¶</a> </dt>

<dd> قسمتی از <a class="reference internal" href="stable.html#stable">ABI پایدار</a>.Parse the parameter of a function that takes a single positional parameter

into a local variable. Returns true on success; on failure, it returns

false and raises the appropriate exception.

Example:

<div class="highlight-c notranslate"><div class="highlight"><pre>// Function using METH_O calling convention

static PyObject*

my_function(PyObject *module, PyObject *arg)

{

int value;

if (!PyArg_Parse(arg, "i:my_function", &value)) {

return NULL;

}

// ... use value ...

}

</pre></div>

</div>

</dd></dl>

int PyArg_UnpackTuple(<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a> *args, const char *name, <a class="reference internal" href="intro.html#c.Py_ssize_t" title="Py_ssize_t">Py_ssize_t</a> min, <a class="reference internal" href="intro.html#c.Py_ssize_t" title="Py_ssize_t">Py_ssize_t</a> max, ...)<a class="headerlink" href="#c.PyArg_UnpackTuple" title="Link to this definition">¶</a> </dt>

<dd> قسمتی از <a class="reference internal" href="stable.html#stable">ABI پایدار</a>.A simpler form of parameter retrieval which does not use a format string to

specify the types of the arguments. Functions which use this method to retrieve

their parameters should be declared as <a class="reference internal" href="structures.html#c.METH_VARARGS" title="METH_VARARGS"><code class="xref c c-macro docutils literal notranslate">METH_VARARGS</code></a> in function or

method tables. The tuple containing the actual parameters should be passed as

args; it must actually be a tuple. The length of the tuple must be at least

min and no more than max; min and max may be equal. Additional

arguments must be passed to the function, each of which should be a pointer to a

<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* variable; these will be filled in with the values from

args; they will contain <a class="reference internal" href="../glossary.html#term-borrowed-reference">borrowed references</a>.

The variables which correspond

to optional parameters not given by args will not be filled in; these should

be initialized by the caller. This function returns true on success and false if

args is not a tuple or contains the wrong number of elements; an exception

will be set if there was a failure.

This is an example of the use of this function, taken from the sources for the

<code class="xref py py-mod docutils literal notranslate">_weakref</code> helper module for weak references:

<div class="highlight-c notranslate"><div class="highlight"><pre>static PyObject *

weakref_ref(PyObject *self, PyObject *args)

{

PyObject *object;

PyObject *callback = NULL;

PyObject *result = NULL;

if (PyArg_UnpackTuple(args, "ref", 1, 2, &object, &callback)) {

result = PyWeakref_NewRef(object, callback);

}

return result;

}

</pre></div>

</div>

The call to <a class="reference internal" href="#c.PyArg_UnpackTuple" title="PyArg_UnpackTuple"><code class="xref c c-func docutils literal notranslate">PyArg_UnpackTuple()</code></a> in this example is entirely equivalent to

this call to <a class="reference internal" href="#c.PyArg_ParseTuple" title="PyArg_ParseTuple"><code class="xref c c-func docutils literal notranslate">PyArg_ParseTuple()</code></a>:

<div class="highlight-c notranslate"><div class="highlight"><pre>PyArg_ParseTuple(args, "O|O:ref", &object, &callback)

</pre></div>

</div>

</dd></dl>

PY_CXX_CONST<a class="headerlink" href="#c.PY_CXX_CONST" title="Link to this definition">¶</a> </dt>

<dd>The value to be inserted, if any, before char *const*

in the keywords parameter declaration of

<a class="reference internal" href="#c.PyArg_VaParseTupleAndKeywords" title="PyArg_VaParseTupleAndKeywords"><code class="xref c c-func docutils literal notranslate">PyArg_VaParseTupleAndKeywords()</code></a>.

Default empty for C and <code class="docutils literal notranslate">const</code> for C++

(const char *const*).

To override, define it to the desired value before including

<code class="file docutils literal notranslate">Python.h</code>.

Added in version 3.13.

</div>

</dd></dl>

</section>

<h2>Building values<a class="headerlink" href="#building-values" title="Link to this heading">¶</a></h2>

<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a> *Py_BuildValue(const char *format, ...)<a class="headerlink" href="#c.Py_BuildValue" title="Link to this definition">¶</a> </dt>

<code class="docutils literal notranslate">PyArg_Parse*</code> family of functions and a sequence of values. Returns

the value or <code class="docutils literal notranslate">NULL</code> in the case of an error; an exception will be raised if

<code class="docutils literal notranslate">NULL</code> is returned.

<a class="reference internal" href="#c.Py_BuildValue" title="Py_BuildValue"><code class="xref c c-func docutils literal notranslate">Py_BuildValue()</code></a> does not always build a tuple. It builds a tuple only if

its format string contains two or more format units. If the format string is

empty, it returns <code class="docutils literal notranslate">None</code>; if it contains exactly one format unit, it returns

whatever object is described by that format unit. To force it to return a tuple

of size 0 or one, parenthesize the format string.

When memory buffers are passed as parameters to supply data to build objects, as

for the <code class="docutils literal notranslate">s</code> and <code class="docutils literal notranslate">s#</code> formats, the required data is copied. Buffers provided

by the caller are never referenced by the objects created by

<a class="reference internal" href="#c.Py_BuildValue" title="Py_BuildValue"><code class="xref c c-func docutils literal notranslate">Py_BuildValue()</code></a>. In other words, if your code invokes <code class="xref c c-func docutils literal notranslate">malloc()</code>

and passes the allocated memory to <code class="xref c c-func docutils literal notranslate">Py_BuildValue()</code>, your code is

responsible for calling <code class="xref c c-func docutils literal notranslate">free()</code> for that memory once

<code class="xref c c-func docutils literal notranslate">Py_BuildValue()</code> returns.

In the following description, the quoted form is the format unit; the entry in

(round) parentheses is the Python object type that the format unit will return;

and the entry in [square] brackets is the type of the C value(s) to be passed.

The characters space, tab, colon and comma are ignored in format strings (but

not within format units such as <code class="docutils literal notranslate">s#</code>). This can be used to make long format

strings a tad more readable.

<dt><code class="docutils literal notranslate">s</code> (<a class="reference internal" href="../library/stdtypes.html#str" title="str"><code class="xref py py-class docutils literal notranslate">str</code></a> or <code class="docutils literal notranslate">None</code>) [const char *]</dt><dd>Convert a null-terminated C string to a Python <a class="reference internal" href="../library/stdtypes.html#str" title="str"><code class="xref py py-class docutils literal notranslate">str</code></a> object using <code class="docutils literal notranslate">'utf-8'</code>

encoding. If the C string pointer is <code class="docutils literal notranslate">NULL</code>, <code class="docutils literal notranslate">None</code> is used.

</dd>

<dt><code class="docutils literal notranslate">s#</code> (<a class="reference internal" href="../library/stdtypes.html#str" title="str"><code class="xref py py-class docutils literal notranslate">str</code></a> or <code class="docutils literal notranslate">None</code>) [const char *, <a class="reference internal" href="intro.html#c.Py_ssize_t" title="Py_ssize_t"><code class="xref c c-type docutils literal notranslate">Py_ssize_t</code></a>]</dt><dd>Convert a C string and its length to a Python <a class="reference internal" href="../library/stdtypes.html#str" title="str"><code class="xref py py-class docutils literal notranslate">str</code></a> object using <code class="docutils literal notranslate">'utf-8'</code>

encoding. If the C string pointer is <code class="docutils literal notranslate">NULL</code>, the length is ignored and

<code class="docutils literal notranslate">None</code> is returned.

</dd>

<dt><code class="docutils literal notranslate">y</code> (<a class="reference internal" href="../library/stdtypes.html#bytes" title="bytes"><code class="xref py py-class docutils literal notranslate">bytes</code></a>) [const char *]</dt><dd>This converts a C string to a Python <a class="reference internal" href="../library/stdtypes.html#bytes" title="bytes"><code class="xref py py-class docutils literal notranslate">bytes</code></a> object. If the C

string pointer is <code class="docutils literal notranslate">NULL</code>, <code class="docutils literal notranslate">None</code> is returned.

</dd>

<dt><code class="docutils literal notranslate">y#</code> (<a class="reference internal" href="../library/stdtypes.html#bytes" title="bytes"><code class="xref py py-class docutils literal notranslate">bytes</code></a>) [const char *, <a class="reference internal" href="intro.html#c.Py_ssize_t" title="Py_ssize_t"><code class="xref c c-type docutils literal notranslate">Py_ssize_t</code></a>]</dt><dd>This converts a C string and its lengths to a Python object. If the C

string pointer is <code class="docutils literal notranslate">NULL</code>, <code class="docutils literal notranslate">None</code> is returned.

</dd>

<dt><code class="docutils literal notranslate">z</code> (<a class="reference internal" href="../library/stdtypes.html#str" title="str"><code class="xref py py-class docutils literal notranslate">str</code></a> or <code class="docutils literal notranslate">None</code>) [const char *]</dt><dd>Same as <code class="docutils literal notranslate">s</code>.

</dd>

<dt><code class="docutils literal notranslate">u</code> (<a class="reference internal" href="../library/stdtypes.html#str" title="str"><code class="xref py py-class docutils literal notranslate">str</code></a>) [const wchar_t *]</dt><dd>Convert a null-terminated <code class="xref c c-type docutils literal notranslate">wchar_t</code> buffer of Unicode (UTF-16 or UCS-4)

data to a Python Unicode object. If the Unicode buffer pointer is <code class="docutils literal notranslate">NULL</code>,

<code class="docutils literal notranslate">None</code> is returned.

</dd>

<dt><code class="docutils literal notranslate">u#</code> (<a class="reference internal" href="../library/stdtypes.html#str" title="str"><code class="xref py py-class docutils literal notranslate">str</code></a>) [const wchar_t *, <a class="reference internal" href="intro.html#c.Py_ssize_t" title="Py_ssize_t"><code class="xref c c-type docutils literal notranslate">Py_ssize_t</code></a>]</dt><dd>Convert a Unicode (UTF-16 or UCS-4) data buffer and its length to a Python

Unicode object. If the Unicode buffer pointer is <code class="docutils literal notranslate">NULL</code>, the length is ignored

and <code class="docutils literal notranslate">None</code> is returned.

</dd>

<dt><code class="docutils literal notranslate">U</code> (<a class="reference internal" href="../library/stdtypes.html#str" title="str"><code class="xref py py-class docutils literal notranslate">str</code></a> or <code class="docutils literal notranslate">None</code>) [const char *]</dt><dd>Same as <code class="docutils literal notranslate">s</code>.

</dd>

<dt><code class="docutils literal notranslate">U#</code> (<a class="reference internal" href="../library/stdtypes.html#str" title="str"><code class="xref py py-class docutils literal notranslate">str</code></a> or <code class="docutils literal notranslate">None</code>) [const char *, <a class="reference internal" href="intro.html#c.Py_ssize_t" title="Py_ssize_t"><code class="xref c c-type docutils literal notranslate">Py_ssize_t</code></a>]</dt><dd>Same as <code class="docutils literal notranslate">s#</code>.

</dd>

<dt><code class="docutils literal notranslate">i</code> (<a class="reference internal" href="../library/functions.html#int" title="int"><code class="xref py py-class docutils literal notranslate">int</code></a>) [int]</dt><dd>Convert a plain C int to a Python integer object.

</dd>

<dt><code class="docutils literal notranslate">b</code> (<a class="reference internal" href="../library/functions.html#int" title="int"><code class="xref py py-class docutils literal notranslate">int</code></a>) [char]</dt><dd>Convert a plain C char to a Python integer object.

</dd>

<dt><code class="docutils literal notranslate">h</code> (<a class="reference internal" href="../library/functions.html#int" title="int"><code class="xref py py-class docutils literal notranslate">int</code></a>) [short int]</dt><dd>Convert a plain C short int to a Python integer object.

</dd>

<dt><code class="docutils literal notranslate">l</code> (<a class="reference internal" href="../library/functions.html#int" title="int"><code class="xref py py-class docutils literal notranslate">int</code></a>) [long int]</dt><dd>Convert a C long int to a Python integer object.

</dd>

<dt><code class="docutils literal notranslate">B</code> (<a class="reference internal" href="../library/functions.html#int" title="int"><code class="xref py py-class docutils literal notranslate">int</code></a>) [unsigned char]</dt><dd>Convert a C unsigned char to a Python integer object.

</dd>

<dt><code class="docutils literal notranslate">H</code> (<a class="reference internal" href="../library/functions.html#int" title="int"><code class="xref py py-class docutils literal notranslate">int</code></a>) [unsigned short int]</dt><dd>Convert a C unsigned short int to a Python integer object.

</dd>

<dt><code class="docutils literal notranslate">I</code> (<a class="reference internal" href="../library/functions.html#int" title="int"><code class="xref py py-class docutils literal notranslate">int</code></a>) [unsigned int]</dt><dd>Convert a C unsigned int to a Python integer object.

</dd>

<dt><code class="docutils literal notranslate">k</code> (<a class="reference internal" href="../library/functions.html#int" title="int"><code class="xref py py-class docutils literal notranslate">int</code></a>) [unsigned long]</dt><dd>Convert a C unsigned long to a Python integer object.

</dd>

<dt><code class="docutils literal notranslate">L</code> (<a class="reference internal" href="../library/functions.html#int" title="int"><code class="xref py py-class docutils literal notranslate">int</code></a>) [long long]</dt><dd>Convert a C long long to a Python integer object.

</dd>

</dl>

<dt><code class="docutils literal notranslate">K</code> (<a class="reference internal" href="../library/functions.html#int" title="int"><code class="xref py py-class docutils literal notranslate">int</code></a>) [unsigned long long]</dt><dd>Convert a C unsigned long long to a Python integer object.

</dd>

<dt><code class="docutils literal notranslate">n</code> (<a class="reference internal" href="../library/functions.html#int" title="int"><code class="xref py py-class docutils literal notranslate">int</code></a>) [<a class="reference internal" href="intro.html#c.Py_ssize_t" title="Py_ssize_t"><code class="xref c c-type docutils literal notranslate">Py_ssize_t</code></a>]</dt><dd>Convert a C <a class="reference internal" href="intro.html#c.Py_ssize_t" title="Py_ssize_t"><code class="xref c c-type docutils literal notranslate">Py_ssize_t</code></a> to a Python integer.

</dd>

<dt><code class="docutils literal notranslate">p</code> (<a class="reference internal" href="../library/functions.html#bool" title="bool"><code class="xref py py-class docutils literal notranslate">bool</code></a>) [int]</dt><dd>Convert a C int to a Python <a class="reference internal" href="../library/functions.html#bool" title="bool"><code class="xref py py-class docutils literal notranslate">bool</code></a> object.

Be aware that this format requires an <code class="docutils literal notranslate">int</code> argument.

Unlike most other contexts in C, variadic arguments are not coerced to

a suitable type automatically.

You can convert another type (for example, a pointer or a float) to a

suitable <code class="docutils literal notranslate">int</code> value using <code class="docutils literal notranslate">(x) ? 1 : 0</code> or <code class="docutils literal notranslate">!!x</code>.

Added in version 3.14.

</div>

</dd>

<dt><code class="docutils literal notranslate">c</code> (<a class="reference internal" href="../library/stdtypes.html#bytes" title="bytes"><code class="xref py py-class docutils literal notranslate">bytes</code></a> of length 1) [char]</dt><dd>Convert a C int representing a byte to a Python <a class="reference internal" href="../library/stdtypes.html#bytes" title="bytes"><code class="xref py py-class docutils literal notranslate">bytes</code></a> object of

length 1.

</dd>

<dt><code class="docutils literal notranslate">C</code> (<a class="reference internal" href="../library/stdtypes.html#str" title="str"><code class="xref py py-class docutils literal notranslate">str</code></a> of length 1) [int]</dt><dd>Convert a C int representing a character to Python <a class="reference internal" href="../library/stdtypes.html#str" title="str"><code class="xref py py-class docutils literal notranslate">str</code></a>

object of length 1.

</dd>

<dt><code class="docutils literal notranslate">d</code> (<a class="reference internal" href="../library/functions.html#float" title="float"><code class="xref py py-class docutils literal notranslate">float</code></a>) [double]</dt><dd>Convert a C double to a Python floating-point number.

</dd>

<dt><code class="docutils literal notranslate">f</code> (<a class="reference internal" href="../library/functions.html#float" title="float"><code class="xref py py-class docutils literal notranslate">float</code></a>) [float]</dt><dd>Convert a C float to a Python floating-point number.

</dd>

<dt><code class="docutils literal notranslate">D</code> (<a class="reference internal" href="../library/functions.html#complex" title="complex"><code class="xref py py-class docutils literal notranslate">complex</code></a>) [Py_complex *]</dt><dd>Convert a C <a class="reference internal" href="complex.html#c.Py_complex" title="Py_complex"><code class="xref c c-type docutils literal notranslate">Py_complex</code></a> structure to a Python complex number.

</dd>

<dt><code class="docutils literal notranslate">O</code> (object) [PyObject *]</dt><dd>Pass a Python object untouched but create a new

<a class="reference internal" href="../glossary.html#term-strong-reference">strong reference</a> to it

(i.e. its reference count is incremented by one).

If the object passed in is a <code class="docutils literal notranslate">NULL</code> pointer, it is assumed

that this was caused because the call producing the argument found an error and

set an exception. Therefore, <a class="reference internal" href="#c.Py_BuildValue" title="Py_BuildValue"><code class="xref c c-func docutils literal notranslate">Py_BuildValue()</code></a> will return <code class="docutils literal notranslate">NULL</code> but won't

raise an exception. If no exception has been raised yet, <a class="reference internal" href="../library/exceptions.html#SystemError" title="SystemError"><code class="xref py py-exc docutils literal notranslate">SystemError</code></a> is

set.

</dd>

<dt><code class="docutils literal notranslate">S</code> (object) [PyObject *]</dt><dd>Same as <code class="docutils literal notranslate">O</code>.

</dd>

<dt><code class="docutils literal notranslate">N</code> (object) [PyObject *]</dt><dd>Same as <code class="docutils literal notranslate">O</code>, except it doesn't create a new <a class="reference internal" href="../glossary.html#term-strong-reference">strong reference</a>.

Useful when the object is created by a call to an object constructor in the

argument list.

</dd>

<dt><code class="docutils literal notranslate">O&</code> (object) [converter, anything]</dt><dd>Convert anything to a Python object through a converter function. The

function is called with anything (which should be compatible with void*)

as its argument and should return a "new" Python object, or <code class="docutils literal notranslate">NULL</code> if an

error occurred.

</dd>

<dt><code class="docutils literal notranslate">(items)</code> (<a class="reference internal" href="../library/stdtypes.html#tuple" title="tuple"><code class="xref py py-class docutils literal notranslate">tuple</code></a>) [matching-items]</dt><dd>Convert a sequence of C values to a Python tuple with the same number of items.

</dd>

<dt><code class="docutils literal notranslate">[items]</code> (<a class="reference internal" href="../library/stdtypes.html#list" title="list"><code class="xref py py-class docutils literal notranslate">list</code></a>) [matching-items]</dt><dd>Convert a sequence of C values to a Python list with the same number of items.

</dd>

<dt><code class="docutils literal notranslate">{items}</code> (<a class="reference internal" href="../library/stdtypes.html#dict" title="dict"><code class="xref py py-class docutils literal notranslate">dict</code></a>) [matching-items]</dt><dd>Convert a sequence of C values to a Python dictionary. Each pair of consecutive

C values adds one item to the dictionary, serving as key and value,

respectively.

</dd>

</dl>

If there is an error in the format string, the <a class="reference internal" href="../library/exceptions.html#SystemError" title="SystemError"><code class="xref py py-exc docutils literal notranslate">SystemError</code></a> exception is

set and <code class="docutils literal notranslate">NULL</code> returned.

</dd></dl>

<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a> *Py_VaBuildValue(const char *format, va_list vargs)<a class="headerlink" href="#c.Py_VaBuildValue" title="Link to this definition">¶</a> </dt>

<dd>مقدار بازگشتی: مرجع جدید. قسمتی از <a class="reference internal" href="stable.html#stable">ABI پایدار</a>.Identical to <a class="reference internal" href="#c.Py_BuildValue" title="Py_BuildValue"><code class="xref c c-func docutils literal notranslate">Py_BuildValue()</code></a>, except that it accepts a va_list

rather than a variable number of arguments.

</dd></dl>

</section>

</div>

<div>

<h3><a href="../contents.html">فهرست عناوین</a></h3>

<ul>

<li><a class="reference internal" href="#">Parsing arguments and building values</a><ul>

<li><a class="reference internal" href="#parsing-arguments">Parsing arguments</a><ul>

<li><a class="reference internal" href="#strings-and-buffers">Strings and buffers</a></li>

<li><a class="reference internal" href="#numbers">Numbers</a></li>

<li><a class="reference internal" href="#other-objects">Other objects</a></li>

<li><a class="reference internal" href="#api-functions">API Functions</a></li>

</ul>

</li>

<li><a class="reference internal" href="#building-values">Building values</a></li>

</ul>

</li>

</ul>

</div>

<div>

<h4>موضوع قبلی</h4>

<a href="marshal.html"

title="فصل قبلی">Data marshalling support</a>

</div>

<div>

<h4>موضوع بعدی</h4>

<a href="conversion.html"

title="فصل بعدی">String conversion and formatting</a>

</div>

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