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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="X-UA-Compatible" content="IE=Edge" /> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>Object Protocol — Python 2.7.18 documentation</title> <link rel="stylesheet" href="../_static/classic.css" type="text/css" /> <link rel="stylesheet" href="../_static/pygments.css" type="text/css" /> <script type="text/javascript" id="documentation_options" data-url_root="../" src="../_static/documentation_options.js"></script> <script type="text/javascript" src="../_static/jquery.js"></script> <script type="text/javascript" src="../_static/underscore.js"></script> <script type="text/javascript" src="../_static/doctools.js"></script> <script type="text/javascript" src="../_static/language_data.js"></script> <script type="text/javascript" src="../_static/sidebar.js"></script> <link rel="search" type="application/opensearchdescription+xml" title="Search within Python 2.7.18 documentation" href="../_static/opensearch.xml"/> <link rel="author" title="About these documents" href="../about.html" /> <link rel="index" title="Index" href="../genindex.html" /> <link rel="search" title="Search" href="../search.html" /> <link rel="copyright" title="Copyright" href="../copyright.html" /> <link rel="next" title="Number Protocol" href="number.html" /> <link rel="prev" title="Abstract Objects Layer" href="abstract.html" /> <link rel="shortcut icon" type="image/png" href="../_static/py.png" /> <link rel="canonical" href="file:///usr/share/doc/python2.7/html/c-api/object.html" /> <script type="text/javascript" src="../_static/copybutton.js"></script> </head><body> <div id="outdated-warning" style="padding: .5em; text-align: center; background-color: #FFBABA; color: #6A0E0E;"> This document is for an old version of Python that is <a href="https://devguide.python.org/devcycle/#end-of-life-branches">no longer supported</a>. You should install the python3 and python3-doc packages and read the <a href="file:///usr/share/doc/python3-doc/html/c-api/object.html"> Python documentation for the Python3 version packaged in this release</a>. </div> <div class="related" role="navigation" aria-label="related navigation"> <h3>Navigation</h3> <ul> <li class="right" style="margin-right: 10px"> <a href="../genindex.html" title="General Index" accesskey="I">index</a></li> <li class="right" > <a href="../py-modindex.html" title="Python Module Index" >modules</a> |</li> <li class="right" > <a href="number.html" title="Number Protocol" accesskey="N">next</a> |</li> <li class="right" > <a href="abstract.html" title="Abstract Objects Layer" accesskey="P">previous</a> |</li> <li><img src="../_static/py.png" alt="" style="vertical-align: middle; margin-top: -1px"/></li> <li><a href="https://www.python.org/">Python</a> »</li> <li> <a href="../index.html">Python 2.7.18 documentation</a> » </li> <li class="nav-item nav-item-1"><a href="index.html" >Python/C API Reference Manual</a> »</li> <li class="nav-item nav-item-2"><a href="abstract.html" accesskey="U">Abstract Objects Layer</a> »</li> </ul> </div> <div class="document"> <div class="documentwrapper"> <div class="bodywrapper"> <div class="body" role="main"> <div class="section" id="object-protocol"> <span id="object"></span><h1>Object Protocol<a class="headerlink" href="#object-protocol" title="Permalink to this headline">¶</a></h1> <dl class="function"> <dt id="c.PyObject_Print"> int <code class="descname">PyObject_Print</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em>, FILE<em> *fp</em>, int<em> flags</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_Print" title="Permalink to this definition">¶</a></dt> <dd><p>Print an object <em>o</em>, on file <em>fp</em>. Returns <code class="docutils literal notranslate"><span class="pre">-1</span></code> on error. The flags argument is used to enable certain printing options. The only option currently supported is <code class="xref py py-const docutils literal notranslate"><span class="pre">Py_PRINT_RAW</span></code>; if given, the <a class="reference internal" href="../library/functions.html#str" title="str"><code class="xref py py-func docutils literal notranslate"><span class="pre">str()</span></code></a> of the object is written instead of the <a class="reference internal" href="../library/functions.html#repr" title="repr"><code class="xref py py-func docutils literal notranslate"><span class="pre">repr()</span></code></a>.</p> </dd></dl> <dl class="function"> <dt id="c.PyObject_HasAttr"> int <code class="descname">PyObject_HasAttr</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *attr_name</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_HasAttr" title="Permalink to this definition">¶</a></dt> <dd><p>Returns <code class="docutils literal notranslate"><span class="pre">1</span></code> if <em>o</em> has the attribute <em>attr_name</em>, and <code class="docutils literal notranslate"><span class="pre">0</span></code> otherwise. This is equivalent to the Python expression <code class="docutils literal notranslate"><span class="pre">hasattr(o,</span> <span class="pre">attr_name)</span></code>. This function always succeeds.</p> </dd></dl> <dl class="function"> <dt id="c.PyObject_HasAttrString"> int <code class="descname">PyObject_HasAttrString</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em>, const char<em> *attr_name</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_HasAttrString" title="Permalink to this definition">¶</a></dt> <dd><p>Returns <code class="docutils literal notranslate"><span class="pre">1</span></code> if <em>o</em> has the attribute <em>attr_name</em>, and <code class="docutils literal notranslate"><span class="pre">0</span></code> otherwise. This is equivalent to the Python expression <code class="docutils literal notranslate"><span class="pre">hasattr(o,</span> <span class="pre">attr_name)</span></code>. This function always succeeds.</p> </dd></dl> <dl class="function"> <dt id="c.PyObject_GetAttr"> <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyObject_GetAttr</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *attr_name</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_GetAttr" title="Permalink to this definition">¶</a></dt> <dd><em class="refcount">Return value: New reference.</em><p>Retrieve an attribute named <em>attr_name</em> from object <em>o</em>. Returns the attribute value on success, or <em>NULL</em> on failure. This is the equivalent of the Python expression <code class="docutils literal notranslate"><span class="pre">o.attr_name</span></code>.</p> </dd></dl> <dl class="function"> <dt id="c.PyObject_GetAttrString"> <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyObject_GetAttrString</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em>, const char<em> *attr_name</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_GetAttrString" title="Permalink to this definition">¶</a></dt> <dd><em class="refcount">Return value: New reference.</em><p>Retrieve an attribute named <em>attr_name</em> from object <em>o</em>. Returns the attribute value on success, or <em>NULL</em> on failure. This is the equivalent of the Python expression <code class="docutils literal notranslate"><span class="pre">o.attr_name</span></code>.</p> </dd></dl> <dl class="function"> <dt id="c.PyObject_GenericGetAttr"> <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyObject_GenericGetAttr</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *name</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_GenericGetAttr" title="Permalink to this definition">¶</a></dt> <dd><p>Generic attribute getter function that is meant to be put into a type object’s <code class="docutils literal notranslate"><span class="pre">tp_getattro</span></code> slot. It looks for a descriptor in the dictionary of classes in the object’s MRO as well as an attribute in the object’s <a class="reference internal" href="../library/stdtypes.html#object.__dict__" title="object.__dict__"><code class="xref py py-attr docutils literal notranslate"><span class="pre">__dict__</span></code></a> (if present). As outlined in <a class="reference internal" href="../reference/datamodel.html#descriptors"><span class="std std-ref">Implementing Descriptors</span></a>, data descriptors take preference over instance attributes, while non-data descriptors don’t. Otherwise, an <a class="reference internal" href="../library/exceptions.html#exceptions.AttributeError" title="exceptions.AttributeError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">AttributeError</span></code></a> is raised.</p> </dd></dl> <dl class="function"> <dt id="c.PyObject_SetAttr"> int <code class="descname">PyObject_SetAttr</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *attr_name</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *v</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_SetAttr" title="Permalink to this definition">¶</a></dt> <dd><p>Set the value of the attribute named <em>attr_name</em>, for object <em>o</em>, to the value <em>v</em>. Raise an exception and return <code class="docutils literal notranslate"><span class="pre">-1</span></code> on failure; return <code class="docutils literal notranslate"><span class="pre">0</span></code> on success. This is the equivalent of the Python statement <code class="docutils literal notranslate"><span class="pre">o.attr_name</span> <span class="pre">=</span> <span class="pre">v</span></code>.</p> <p>If <em>v</em> is <em>NULL</em>, the attribute is deleted, however this feature is deprecated in favour of using <a class="reference internal" href="#c.PyObject_DelAttr" title="PyObject_DelAttr"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyObject_DelAttr()</span></code></a>.</p> </dd></dl> <dl class="function"> <dt id="c.PyObject_SetAttrString"> int <code class="descname">PyObject_SetAttrString</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em>, const char<em> *attr_name</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *v</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_SetAttrString" title="Permalink to this definition">¶</a></dt> <dd><p>Set the value of the attribute named <em>attr_name</em>, for object <em>o</em>, to the value <em>v</em>. Raise an exception and return <code class="docutils literal notranslate"><span class="pre">-1</span></code> on failure; return <code class="docutils literal notranslate"><span class="pre">0</span></code> on success. This is the equivalent of the Python statement <code class="docutils literal notranslate"><span class="pre">o.attr_name</span> <span class="pre">=</span> <span class="pre">v</span></code>.</p> <p>If <em>v</em> is <em>NULL</em>, the attribute is deleted, however this feature is deprecated in favour of using <a class="reference internal" href="#c.PyObject_DelAttrString" title="PyObject_DelAttrString"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyObject_DelAttrString()</span></code></a>.</p> </dd></dl> <dl class="function"> <dt id="c.PyObject_GenericSetAttr"> int <code class="descname">PyObject_GenericSetAttr</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *name</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *value</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_GenericSetAttr" title="Permalink to this definition">¶</a></dt> <dd><p>Generic attribute setter and deleter function that is meant to be put into a type object’s <a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_setattro" title="PyTypeObject.tp_setattro"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_setattro</span></code></a> slot. It looks for a data descriptor in the dictionary of classes in the object’s MRO, and if found it takes preference over setting or deleting the attribute in the instance dictionary. Otherwise, the attribute is set or deleted in the object’s <a class="reference internal" href="../library/stdtypes.html#object.__dict__" title="object.__dict__"><code class="xref py py-attr docutils literal notranslate"><span class="pre">__dict__</span></code></a> (if present). On success, <code class="docutils literal notranslate"><span class="pre">0</span></code> is returned, otherwise an <a class="reference internal" href="../library/exceptions.html#exceptions.AttributeError" title="exceptions.AttributeError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">AttributeError</span></code></a> is raised and <code class="docutils literal notranslate"><span class="pre">-1</span></code> is returned.</p> </dd></dl> <dl class="function"> <dt id="c.PyObject_DelAttr"> int <code class="descname">PyObject_DelAttr</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *attr_name</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_DelAttr" title="Permalink to this definition">¶</a></dt> <dd><p>Delete attribute named <em>attr_name</em>, for object <em>o</em>. Returns <code class="docutils literal notranslate"><span class="pre">-1</span></code> on failure. This is the equivalent of the Python statement <code class="docutils literal notranslate"><span class="pre">del</span> <span class="pre">o.attr_name</span></code>.</p> </dd></dl> <dl class="function"> <dt id="c.PyObject_DelAttrString"> int <code class="descname">PyObject_DelAttrString</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em>, const char<em> *attr_name</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_DelAttrString" title="Permalink to this definition">¶</a></dt> <dd><p>Delete attribute named <em>attr_name</em>, for object <em>o</em>. Returns <code class="docutils literal notranslate"><span class="pre">-1</span></code> on failure. This is the equivalent of the Python statement <code class="docutils literal notranslate"><span class="pre">del</span> <span class="pre">o.attr_name</span></code>.</p> </dd></dl> <dl class="function"> <dt id="c.PyObject_RichCompare"> <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyObject_RichCompare</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o1</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o2</em>, int<em> opid</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_RichCompare" title="Permalink to this definition">¶</a></dt> <dd><em class="refcount">Return value: New reference.</em><p>Compare the values of <em>o1</em> and <em>o2</em> using the operation specified by <em>opid</em>, which must be one of <code class="xref py py-const docutils literal notranslate"><span class="pre">Py_LT</span></code>, <code class="xref py py-const docutils literal notranslate"><span class="pre">Py_LE</span></code>, <code class="xref py py-const docutils literal notranslate"><span class="pre">Py_EQ</span></code>, <code class="xref py py-const docutils literal notranslate"><span class="pre">Py_NE</span></code>, <code class="xref py py-const docutils literal notranslate"><span class="pre">Py_GT</span></code>, or <code class="xref py py-const docutils literal notranslate"><span class="pre">Py_GE</span></code>, corresponding to <code class="docutils literal notranslate"><span class="pre"><</span></code>, <code class="docutils literal notranslate"><span class="pre"><=</span></code>, <code class="docutils literal notranslate"><span class="pre">==</span></code>, <code class="docutils literal notranslate"><span class="pre">!=</span></code>, <code class="docutils literal notranslate"><span class="pre">></span></code>, or <code class="docutils literal notranslate"><span class="pre">>=</span></code> respectively. This is the equivalent of the Python expression <code class="docutils literal notranslate"><span class="pre">o1</span> <span class="pre">op</span> <span class="pre">o2</span></code>, where <code class="docutils literal notranslate"><span class="pre">op</span></code> is the operator corresponding to <em>opid</em>. Returns the value of the comparison on success, or <em>NULL</em> on failure.</p> </dd></dl> <dl class="function"> <dt id="c.PyObject_RichCompareBool"> int <code class="descname">PyObject_RichCompareBool</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o1</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o2</em>, int<em> opid</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_RichCompareBool" title="Permalink to this definition">¶</a></dt> <dd><p>Compare the values of <em>o1</em> and <em>o2</em> using the operation specified by <em>opid</em>, which must be one of <code class="xref py py-const docutils literal notranslate"><span class="pre">Py_LT</span></code>, <code class="xref py py-const docutils literal notranslate"><span class="pre">Py_LE</span></code>, <code class="xref py py-const docutils literal notranslate"><span class="pre">Py_EQ</span></code>, <code class="xref py py-const docutils literal notranslate"><span class="pre">Py_NE</span></code>, <code class="xref py py-const docutils literal notranslate"><span class="pre">Py_GT</span></code>, or <code class="xref py py-const docutils literal notranslate"><span class="pre">Py_GE</span></code>, corresponding to <code class="docutils literal notranslate"><span class="pre"><</span></code>, <code class="docutils literal notranslate"><span class="pre"><=</span></code>, <code class="docutils literal notranslate"><span class="pre">==</span></code>, <code class="docutils literal notranslate"><span class="pre">!=</span></code>, <code class="docutils literal notranslate"><span class="pre">></span></code>, or <code class="docutils literal notranslate"><span class="pre">>=</span></code> respectively. Returns <code class="docutils literal notranslate"><span class="pre">-1</span></code> on error, <code class="docutils literal notranslate"><span class="pre">0</span></code> if the result is false, <code class="docutils literal notranslate"><span class="pre">1</span></code> otherwise. This is the equivalent of the Python expression <code class="docutils literal notranslate"><span class="pre">o1</span> <span class="pre">op</span> <span class="pre">o2</span></code>, where <code class="docutils literal notranslate"><span class="pre">op</span></code> is the operator corresponding to <em>opid</em>.</p> </dd></dl> <div class="admonition note"> <p class="first admonition-title">Note</p> <p class="last">If <em>o1</em> and <em>o2</em> are the same object, <a class="reference internal" href="#c.PyObject_RichCompareBool" title="PyObject_RichCompareBool"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyObject_RichCompareBool()</span></code></a> will always return <code class="docutils literal notranslate"><span class="pre">1</span></code> for <code class="xref py py-const docutils literal notranslate"><span class="pre">Py_EQ</span></code> and <code class="docutils literal notranslate"><span class="pre">0</span></code> for <code class="xref py py-const docutils literal notranslate"><span class="pre">Py_NE</span></code>.</p> </div> <dl class="function"> <dt id="c.PyObject_Cmp"> int <code class="descname">PyObject_Cmp</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o1</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o2</em>, int<em> *result</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_Cmp" title="Permalink to this definition">¶</a></dt> <dd><p id="index-0">Compare the values of <em>o1</em> and <em>o2</em> using a routine provided by <em>o1</em>, if one exists, otherwise with a routine provided by <em>o2</em>. The result of the comparison is returned in <em>result</em>. Returns <code class="docutils literal notranslate"><span class="pre">-1</span></code> on failure. This is the equivalent of the Python statement <code class="docutils literal notranslate"><span class="pre">result</span> <span class="pre">=</span> <span class="pre">cmp(o1,</span> <span class="pre">o2)</span></code>.</p> </dd></dl> <dl class="function"> <dt id="c.PyObject_Compare"> int <code class="descname">PyObject_Compare</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o1</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o2</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_Compare" title="Permalink to this definition">¶</a></dt> <dd><p id="index-1">Compare the values of <em>o1</em> and <em>o2</em> using a routine provided by <em>o1</em>, if one exists, otherwise with a routine provided by <em>o2</em>. Returns the result of the comparison on success. On error, the value returned is undefined; use <a class="reference internal" href="exceptions.html#c.PyErr_Occurred" title="PyErr_Occurred"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyErr_Occurred()</span></code></a> to detect an error. This is equivalent to the Python expression <code class="docutils literal notranslate"><span class="pre">cmp(o1,</span> <span class="pre">o2)</span></code>.</p> </dd></dl> <dl class="function"> <dt id="c.PyObject_Repr"> <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyObject_Repr</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_Repr" title="Permalink to this definition">¶</a></dt> <dd><em class="refcount">Return value: New reference.</em><p id="index-2">Compute a string representation of object <em>o</em>. Returns the string representation on success, <em>NULL</em> on failure. This is the equivalent of the Python expression <code class="docutils literal notranslate"><span class="pre">repr(o)</span></code>. Called by the <a class="reference internal" href="../library/functions.html#repr" title="repr"><code class="xref py py-func docutils literal notranslate"><span class="pre">repr()</span></code></a> built-in function and by reverse quotes.</p> </dd></dl> <dl class="function"> <dt id="c.PyObject_Str"> <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyObject_Str</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_Str" title="Permalink to this definition">¶</a></dt> <dd><em class="refcount">Return value: New reference.</em><p id="index-3">Compute a string representation of object <em>o</em>. Returns the string representation on success, <em>NULL</em> on failure. This is the equivalent of the Python expression <code class="docutils literal notranslate"><span class="pre">str(o)</span></code>. Called by the <a class="reference internal" href="../library/functions.html#str" title="str"><code class="xref py py-func docutils literal notranslate"><span class="pre">str()</span></code></a> built-in function and by the <a class="reference internal" href="../reference/simple_stmts.html#print"><code class="xref std std-keyword docutils literal notranslate"><span class="pre">print</span></code></a> statement.</p> </dd></dl> <dl class="function"> <dt id="c.PyObject_Bytes"> <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyObject_Bytes</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_Bytes" title="Permalink to this definition">¶</a></dt> <dd><p id="index-4">Compute a bytes representation of object <em>o</em>. In 2.x, this is just an alias for <a class="reference internal" href="#c.PyObject_Str" title="PyObject_Str"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyObject_Str()</span></code></a>.</p> </dd></dl> <dl class="function"> <dt id="c.PyObject_Unicode"> <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyObject_Unicode</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_Unicode" title="Permalink to this definition">¶</a></dt> <dd><em class="refcount">Return value: New reference.</em><p id="index-5">Compute a Unicode string representation of object <em>o</em>. Returns the Unicode string representation on success, <em>NULL</em> on failure. This is the equivalent of the Python expression <code class="docutils literal notranslate"><span class="pre">unicode(o)</span></code>. Called by the <a class="reference internal" href="../library/functions.html#unicode" title="unicode"><code class="xref py py-func docutils literal notranslate"><span class="pre">unicode()</span></code></a> built-in function.</p> </dd></dl> <dl class="function"> <dt id="c.PyObject_IsInstance"> int <code class="descname">PyObject_IsInstance</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *inst</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *cls</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_IsInstance" title="Permalink to this definition">¶</a></dt> <dd><p>Returns <code class="docutils literal notranslate"><span class="pre">1</span></code> if <em>inst</em> is an instance of the class <em>cls</em> or a subclass of <em>cls</em>, or <code class="docutils literal notranslate"><span class="pre">0</span></code> if not. On error, returns <code class="docutils literal notranslate"><span class="pre">-1</span></code> and sets an exception. If <em>cls</em> is a type object rather than a class object, <a class="reference internal" href="#c.PyObject_IsInstance" title="PyObject_IsInstance"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyObject_IsInstance()</span></code></a> returns <code class="docutils literal notranslate"><span class="pre">1</span></code> if <em>inst</em> is of type <em>cls</em>. If <em>cls</em> is a tuple, the check will be done against every entry in <em>cls</em>. The result will be <code class="docutils literal notranslate"><span class="pre">1</span></code> when at least one of the checks returns <code class="docutils literal notranslate"><span class="pre">1</span></code>, otherwise it will be <code class="docutils literal notranslate"><span class="pre">0</span></code>. If <em>inst</em> is not a class instance and <em>cls</em> is neither a type object, nor a class object, nor a tuple, <em>inst</em> must have a <a class="reference internal" href="../library/stdtypes.html#instance.__class__" title="instance.__class__"><code class="xref py py-attr docutils literal notranslate"><span class="pre">__class__</span></code></a> attribute — the class relationship of the value of that attribute with <em>cls</em> will be used to determine the result of this function.</p> <div class="versionadded"> <p><span class="versionmodified">New in version 2.1.</span></p> </div> <div class="versionchanged"> <p><span class="versionmodified">Changed in version 2.2: </span>Support for a tuple as the second argument added.</p> </div> </dd></dl> <p>Subclass determination is done in a fairly straightforward way, but includes a wrinkle that implementors of extensions to the class system may want to be aware of. If <code class="xref py py-class docutils literal notranslate"><span class="pre">A</span></code> and <code class="xref py py-class docutils literal notranslate"><span class="pre">B</span></code> are class objects, <code class="xref py py-class docutils literal notranslate"><span class="pre">B</span></code> is a subclass of <code class="xref py py-class docutils literal notranslate"><span class="pre">A</span></code> if it inherits from <code class="xref py py-class docutils literal notranslate"><span class="pre">A</span></code> either directly or indirectly. If either is not a class object, a more general mechanism is used to determine the class relationship of the two objects. When testing if <em>B</em> is a subclass of <em>A</em>, if <em>A</em> is <em>B</em>, <a class="reference internal" href="#c.PyObject_IsSubclass" title="PyObject_IsSubclass"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyObject_IsSubclass()</span></code></a> returns true. If <em>A</em> and <em>B</em> are different objects, <em>B</em>’s <a class="reference internal" href="../library/stdtypes.html#class.__bases__" title="class.__bases__"><code class="xref py py-attr docutils literal notranslate"><span class="pre">__bases__</span></code></a> attribute is searched in a depth-first fashion for <em>A</em> — the presence of the <a class="reference internal" href="../library/stdtypes.html#class.__bases__" title="class.__bases__"><code class="xref py py-attr docutils literal notranslate"><span class="pre">__bases__</span></code></a> attribute is considered sufficient for this determination.</p> <dl class="function"> <dt id="c.PyObject_IsSubclass"> int <code class="descname">PyObject_IsSubclass</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *derived</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *cls</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_IsSubclass" title="Permalink to this definition">¶</a></dt> <dd><p>Returns <code class="docutils literal notranslate"><span class="pre">1</span></code> if the class <em>derived</em> is identical to or derived from the class <em>cls</em>, otherwise returns <code class="docutils literal notranslate"><span class="pre">0</span></code>. In case of an error, returns <code class="docutils literal notranslate"><span class="pre">-1</span></code>. If <em>cls</em> is a tuple, the check will be done against every entry in <em>cls</em>. The result will be <code class="docutils literal notranslate"><span class="pre">1</span></code> when at least one of the checks returns <code class="docutils literal notranslate"><span class="pre">1</span></code>, otherwise it will be <code class="docutils literal notranslate"><span class="pre">0</span></code>. If either <em>derived</em> or <em>cls</em> is not an actual class object (or tuple), this function uses the generic algorithm described above.</p> <div class="versionadded"> <p><span class="versionmodified">New in version 2.1.</span></p> </div> <div class="versionchanged"> <p><span class="versionmodified">Changed in version 2.3: </span>Older versions of Python did not support a tuple as the second argument.</p> </div> </dd></dl> <dl class="function"> <dt id="c.PyCallable_Check"> int <code class="descname">PyCallable_Check</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyCallable_Check" title="Permalink to this definition">¶</a></dt> <dd><p>Determine if the object <em>o</em> is callable. Return <code class="docutils literal notranslate"><span class="pre">1</span></code> if the object is callable and <code class="docutils literal notranslate"><span class="pre">0</span></code> otherwise. This function always succeeds.</p> </dd></dl> <dl class="function"> <dt id="c.PyObject_Call"> <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyObject_Call</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *callable_object</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *args</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *kw</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_Call" title="Permalink to this definition">¶</a></dt> <dd><em class="refcount">Return value: New reference.</em><p id="index-6">Call a callable Python object <em>callable_object</em>, with arguments given by the tuple <em>args</em>, and named arguments given by the dictionary <em>kw</em>. If no named arguments are needed, <em>kw</em> may be <em>NULL</em>. <em>args</em> must not be <em>NULL</em>, use an empty tuple if no arguments are needed. Returns the result of the call on success, or <em>NULL</em> on failure. This is the equivalent of the Python expression <code class="docutils literal notranslate"><span class="pre">apply(callable_object,</span> <span class="pre">args,</span> <span class="pre">kw)</span></code> or <code class="docutils literal notranslate"><span class="pre">callable_object(*args,</span> <span class="pre">**kw)</span></code>.</p> <div class="versionadded"> <p><span class="versionmodified">New in version 2.2.</span></p> </div> </dd></dl> <dl class="function"> <dt id="c.PyObject_CallObject"> <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyObject_CallObject</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *callable_object</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *args</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_CallObject" title="Permalink to this definition">¶</a></dt> <dd><em class="refcount">Return value: New reference.</em><p id="index-7">Call a callable Python object <em>callable_object</em>, with arguments given by the tuple <em>args</em>. If no arguments are needed, then <em>args</em> may be <em>NULL</em>. Returns the result of the call on success, or <em>NULL</em> on failure. This is the equivalent of the Python expression <code class="docutils literal notranslate"><span class="pre">apply(callable_object,</span> <span class="pre">args)</span></code> or <code class="docutils literal notranslate"><span class="pre">callable_object(*args)</span></code>.</p> </dd></dl> <dl class="function"> <dt id="c.PyObject_CallFunction"> <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyObject_CallFunction</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *callable</em>, char<em> *format</em>, ...<span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_CallFunction" title="Permalink to this definition">¶</a></dt> <dd><em class="refcount">Return value: New reference.</em><p id="index-8">Call a callable Python object <em>callable</em>, with a variable number of C arguments. The C arguments are described using a <a class="reference internal" href="arg.html#c.Py_BuildValue" title="Py_BuildValue"><code class="xref c c-func docutils literal notranslate"><span class="pre">Py_BuildValue()</span></code></a> style format string. The format may be <em>NULL</em>, indicating that no arguments are provided. Returns the result of the call on success, or <em>NULL</em> on failure. This is the equivalent of the Python expression <code class="docutils literal notranslate"><span class="pre">apply(callable,</span> <span class="pre">args)</span></code> or <code class="docutils literal notranslate"><span class="pre">callable(*args)</span></code>. Note that if you only pass <a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><code class="xref c c-type docutils literal notranslate"><span class="pre">PyObject</span> <span class="pre">*</span></code></a> args, <a class="reference internal" href="#c.PyObject_CallFunctionObjArgs" title="PyObject_CallFunctionObjArgs"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyObject_CallFunctionObjArgs()</span></code></a> is a faster alternative.</p> </dd></dl> <dl class="function"> <dt id="c.PyObject_CallMethod"> <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyObject_CallMethod</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em>, char<em> *method</em>, char<em> *format</em>, ...<span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_CallMethod" title="Permalink to this definition">¶</a></dt> <dd><em class="refcount">Return value: New reference.</em><p>Call the method named <em>method</em> of object <em>o</em> with a variable number of C arguments. The C arguments are described by a <a class="reference internal" href="arg.html#c.Py_BuildValue" title="Py_BuildValue"><code class="xref c c-func docutils literal notranslate"><span class="pre">Py_BuildValue()</span></code></a> format string that should produce a tuple. The format may be <em>NULL</em>, indicating that no arguments are provided. Returns the result of the call on success, or <em>NULL</em> on failure. This is the equivalent of the Python expression <code class="docutils literal notranslate"><span class="pre">o.method(args)</span></code>. Note that if you only pass <a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><code class="xref c c-type docutils literal notranslate"><span class="pre">PyObject</span> <span class="pre">*</span></code></a> args, <a class="reference internal" href="#c.PyObject_CallMethodObjArgs" title="PyObject_CallMethodObjArgs"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyObject_CallMethodObjArgs()</span></code></a> is a faster alternative.</p> </dd></dl> <dl class="function"> <dt id="c.PyObject_CallFunctionObjArgs"> <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyObject_CallFunctionObjArgs</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *callable</em>, ..., NULL<span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_CallFunctionObjArgs" title="Permalink to this definition">¶</a></dt> <dd><em class="refcount">Return value: New reference.</em><p>Call a callable Python object <em>callable</em>, with a variable number of <a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><code class="xref c c-type docutils literal notranslate"><span class="pre">PyObject*</span></code></a> arguments. The arguments are provided as a variable number of parameters followed by <em>NULL</em>. Returns the result of the call on success, or <em>NULL</em> on failure.</p> <div class="versionadded"> <p><span class="versionmodified">New in version 2.2.</span></p> </div> </dd></dl> <dl class="function"> <dt id="c.PyObject_CallMethodObjArgs"> <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyObject_CallMethodObjArgs</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *name</em>, ..., NULL<span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_CallMethodObjArgs" title="Permalink to this definition">¶</a></dt> <dd><em class="refcount">Return value: New reference.</em><p>Calls a method of the object <em>o</em>, where the name of the method is given as a Python string object in <em>name</em>. It is called with a variable number of <a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><code class="xref c c-type docutils literal notranslate"><span class="pre">PyObject*</span></code></a> arguments. The arguments are provided as a variable number of parameters followed by <em>NULL</em>. Returns the result of the call on success, or <em>NULL</em> on failure.</p> <div class="versionadded"> <p><span class="versionmodified">New in version 2.2.</span></p> </div> </dd></dl> <dl class="function"> <dt id="c.PyObject_Hash"> long <code class="descname">PyObject_Hash</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_Hash" title="Permalink to this definition">¶</a></dt> <dd><p id="index-9">Compute and return the hash value of an object <em>o</em>. On failure, return <code class="docutils literal notranslate"><span class="pre">-1</span></code>. This is the equivalent of the Python expression <code class="docutils literal notranslate"><span class="pre">hash(o)</span></code>.</p> </dd></dl> <dl class="function"> <dt id="c.PyObject_HashNotImplemented"> long <code class="descname">PyObject_HashNotImplemented</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_HashNotImplemented" title="Permalink to this definition">¶</a></dt> <dd><p>Set a <a class="reference internal" href="../library/exceptions.html#exceptions.TypeError" title="exceptions.TypeError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">TypeError</span></code></a> indicating that <code class="docutils literal notranslate"><span class="pre">type(o)</span></code> is not hashable and return <code class="docutils literal notranslate"><span class="pre">-1</span></code>. This function receives special treatment when stored in a <code class="docutils literal notranslate"><span class="pre">tp_hash</span></code> slot, allowing a type to explicitly indicate to the interpreter that it is not hashable.</p> <div class="versionadded"> <p><span class="versionmodified">New in version 2.6.</span></p> </div> </dd></dl> <dl class="function"> <dt id="c.PyObject_IsTrue"> int <code class="descname">PyObject_IsTrue</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_IsTrue" title="Permalink to this definition">¶</a></dt> <dd><p>Returns <code class="docutils literal notranslate"><span class="pre">1</span></code> if the object <em>o</em> is considered to be true, and <code class="docutils literal notranslate"><span class="pre">0</span></code> otherwise. This is equivalent to the Python expression <code class="docutils literal notranslate"><span class="pre">not</span> <span class="pre">not</span> <span class="pre">o</span></code>. On failure, return <code class="docutils literal notranslate"><span class="pre">-1</span></code>.</p> </dd></dl> <dl class="function"> <dt id="c.PyObject_Not"> int <code class="descname">PyObject_Not</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_Not" title="Permalink to this definition">¶</a></dt> <dd><p>Returns <code class="docutils literal notranslate"><span class="pre">0</span></code> if the object <em>o</em> is considered to be true, and <code class="docutils literal notranslate"><span class="pre">1</span></code> otherwise. This is equivalent to the Python expression <code class="docutils literal notranslate"><span class="pre">not</span> <span class="pre">o</span></code>. On failure, return <code class="docutils literal notranslate"><span class="pre">-1</span></code>.</p> </dd></dl> <dl class="function"> <dt id="c.PyObject_Type"> <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyObject_Type</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_Type" title="Permalink to this definition">¶</a></dt> <dd><em class="refcount">Return value: New reference.</em><p id="index-10">When <em>o</em> is non-<em>NULL</em>, returns a type object corresponding to the object type of object <em>o</em>. On failure, raises <a class="reference internal" href="../library/exceptions.html#exceptions.SystemError" title="exceptions.SystemError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">SystemError</span></code></a> and returns <em>NULL</em>. This is equivalent to the Python expression <code class="docutils literal notranslate"><span class="pre">type(o)</span></code>. This function increments the reference count of the return value. There’s really no reason to use this function instead of the common expression <code class="docutils literal notranslate"><span class="pre">o->ob_type</span></code>, which returns a pointer of type <a class="reference internal" href="type.html#c.PyTypeObject" title="PyTypeObject"><code class="xref c c-type docutils literal notranslate"><span class="pre">PyTypeObject*</span></code></a>, except when the incremented reference count is needed.</p> </dd></dl> <dl class="function"> <dt id="c.PyObject_TypeCheck"> int <code class="descname">PyObject_TypeCheck</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em>, <a class="reference internal" href="type.html#c.PyTypeObject" title="PyTypeObject">PyTypeObject</a><em> *type</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_TypeCheck" title="Permalink to this definition">¶</a></dt> <dd><p>Return true if the object <em>o</em> is of type <em>type</em> or a subtype of <em>type</em>. Both parameters must be non-<em>NULL</em>.</p> <div class="versionadded"> <p><span class="versionmodified">New in version 2.2.</span></p> </div> </dd></dl> <dl class="function"> <dt id="c.PyObject_Length"> Py_ssize_t <code class="descname">PyObject_Length</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_Length" title="Permalink to this definition">¶</a></dt> <dt id="c.PyObject_Size"> Py_ssize_t <code class="descname">PyObject_Size</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_Size" title="Permalink to this definition">¶</a></dt> <dd><p id="index-11">Return the length of object <em>o</em>. If the object <em>o</em> provides either the sequence and mapping protocols, the sequence length is returned. On error, <code class="docutils literal notranslate"><span class="pre">-1</span></code> is returned. This is the equivalent to the Python expression <code class="docutils literal notranslate"><span class="pre">len(o)</span></code>.</p> <div class="versionchanged"> <p><span class="versionmodified">Changed in version 2.5: </span>These functions returned an <code class="xref c c-type docutils literal notranslate"><span class="pre">int</span></code> type. This might require changes in your code for properly supporting 64-bit systems.</p> </div> </dd></dl> <dl class="function"> <dt id="c.PyObject_GetItem"> <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyObject_GetItem</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *key</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_GetItem" title="Permalink to this definition">¶</a></dt> <dd><em class="refcount">Return value: New reference.</em><p>Return element of <em>o</em> corresponding to the object <em>key</em> or <em>NULL</em> on failure. This is the equivalent of the Python expression <code class="docutils literal notranslate"><span class="pre">o[key]</span></code>.</p> </dd></dl> <dl class="function"> <dt id="c.PyObject_SetItem"> int <code class="descname">PyObject_SetItem</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *key</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *v</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_SetItem" title="Permalink to this definition">¶</a></dt> <dd><p>Map the object <em>key</em> to the value <em>v</em>. Raise an exception and return <code class="docutils literal notranslate"><span class="pre">-1</span></code> on failure; return <code class="docutils literal notranslate"><span class="pre">0</span></code> on success. This is the equivalent of the Python statement <code class="docutils literal notranslate"><span class="pre">o[key]</span> <span class="pre">=</span> <span class="pre">v</span></code>.</p> </dd></dl> <dl class="function"> <dt id="c.PyObject_DelItem"> int <code class="descname">PyObject_DelItem</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *key</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_DelItem" title="Permalink to this definition">¶</a></dt> <dd><p>Delete the mapping for <em>key</em> from <em>o</em>. Returns <code class="docutils literal notranslate"><span class="pre">-1</span></code> on failure. This is the equivalent of the Python statement <code class="docutils literal notranslate"><span class="pre">del</span> <span class="pre">o[key]</span></code>.</p> </dd></dl> <dl class="function"> <dt id="c.PyObject_AsFileDescriptor"> int <code class="descname">PyObject_AsFileDescriptor</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_AsFileDescriptor" title="Permalink to this definition">¶</a></dt> <dd><p>Derives a file descriptor from a Python object. If the object is an integer or long integer, its value is returned. If not, the object’s <code class="xref py py-meth docutils literal notranslate"><span class="pre">fileno()</span></code> method is called if it exists; the method must return an integer or long integer, which is returned as the file descriptor value. Returns <code class="docutils literal notranslate"><span class="pre">-1</span></code> on failure.</p> </dd></dl> <dl class="function"> <dt id="c.PyObject_Dir"> <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyObject_Dir</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_Dir" title="Permalink to this definition">¶</a></dt> <dd><em class="refcount">Return value: New reference.</em><p>This is equivalent to the Python expression <code class="docutils literal notranslate"><span class="pre">dir(o)</span></code>, returning a (possibly empty) list of strings appropriate for the object argument, or <em>NULL</em> if there was an error. If the argument is <em>NULL</em>, this is like the Python <code class="docutils literal notranslate"><span class="pre">dir()</span></code>, returning the names of the current locals; in this case, if no execution frame is active then <em>NULL</em> is returned but <a class="reference internal" href="exceptions.html#c.PyErr_Occurred" title="PyErr_Occurred"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyErr_Occurred()</span></code></a> will return false.</p> </dd></dl> <dl class="function"> <dt id="c.PyObject_GetIter"> <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyObject_GetIter</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_GetIter" title="Permalink to this definition">¶</a></dt> <dd><em class="refcount">Return value: New reference.</em><p>This is equivalent to the Python expression <code class="docutils literal notranslate"><span class="pre">iter(o)</span></code>. It returns a new iterator for the object argument, or the object itself if the object is already an iterator. Raises <a class="reference internal" href="../library/exceptions.html#exceptions.TypeError" title="exceptions.TypeError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">TypeError</span></code></a> and returns <em>NULL</em> if the object cannot be iterated.</p> </dd></dl> </div> </div> </div> </div> <div class="sphinxsidebar" role="navigation" aria-label="main navigation"> <div class="sphinxsidebarwrapper"> <h4>Previous topic</h4> <p class="topless"><a href="abstract.html" title="previous chapter">Abstract Objects Layer</a></p> <h4>Next topic</h4> <p class="topless"><a href="number.html" title="next chapter">Number Protocol</a></p> <div role="note" aria-label="source link"> <h3>This Page</h3> <ul class="this-page-menu"> <li><a href="../_sources/c-api/object.rst.txt" rel="nofollow">Show Source</a></li> </ul> </div> <div id="searchbox" style="display: none" role="search"> <h3>Quick search</h3> <div class="searchformwrapper"> <form class="search" action="../search.html" method="get"> <input type="text" name="q" /> <input type="submit" value="Go" /> <input type="hidden" name="check_keywords" value="yes" /> <input type="hidden" name="area" value="default" /> </form> </div> </div> <script type="text/javascript">$('#searchbox').show(0);</script> </div> </div> <div class="clearer"></div> </div> <div class="related" role="navigation" aria-label="related navigation"> <h3>Navigation</h3> <ul> <li class="right" style="margin-right: 10px"> <a href="../genindex.html" title="General Index" >index</a></li> <li class="right" > <a href="../py-modindex.html" title="Python Module Index" >modules</a> |</li> <li class="right" > <a href="number.html" title="Number Protocol" >next</a> |</li> <li class="right" > <a href="abstract.html" title="Abstract Objects Layer" >previous</a> |</li> <li><img src="../_static/py.png" alt="" style="vertical-align: middle; margin-top: -1px"/></li> <li><a href="https://www.python.org/">Python</a> »</li> <li> <a href="../index.html">Python 2.7.18 documentation</a> » </li> <li class="nav-item nav-item-1"><a href="index.html" >Python/C API Reference Manual</a> »</li> <li class="nav-item nav-item-2"><a href="abstract.html" >Abstract Objects Layer</a> »</li> </ul> </div> <div class="footer"> © <a href="../copyright.html">Copyright</a> 1990-2024, Python Software Foundation. <br /> The Python Software Foundation is a non-profit corporation. <a href="https://www.python.org/psf/donations/">Please donate.</a> <br /> Last updated on December 09, 2024. <a href="../bugs.html">Found a bug</a>? <br /> Created using <a href="http://sphinx.pocoo.org/">Sphinx</a> 1.8.5. </div> </body> </html>