EVOLUTION-NINJA
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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>Sequence Protocol — Python 2.7.16 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/sidebar.js"></script> <link rel="search" type="application/opensearchdescription+xml" title="Search within Python 2.7.16 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="Mapping Protocol" href="mapping.html" /> <link rel="prev" title="Number Protocol" href="number.html" /> <link rel="shortcut icon" type="image/png" href="../_static/py.png" /> <link rel="canonical" href="https://docs.python.org/2/c-api/sequence.html" /> <script type="text/javascript" src="../_static/copybutton.js"></script> </head><body> <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="mapping.html" title="Mapping Protocol" accesskey="N">next</a> |</li> <li class="right" > <a href="number.html" title="Number Protocol" 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 2.7.16 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="sequence-protocol"> <span id="sequence"></span><h1>Sequence Protocol<a class="headerlink" href="#sequence-protocol" title="Permalink to this headline">¶</a></h1> <dl class="function"> <dt id="c.PySequence_Check"> int <code class="descname">PySequence_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.PySequence_Check" title="Permalink to this definition">¶</a></dt> <dd><p>Return <code class="docutils literal notranslate"><span class="pre">1</span></code> if the object provides sequence protocol, 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.PySequence_Size"> Py_ssize_t <code class="descname">PySequence_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.PySequence_Size" title="Permalink to this definition">¶</a></dt> <dt id="c.PySequence_Length"> Py_ssize_t <code class="descname">PySequence_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.PySequence_Length" title="Permalink to this definition">¶</a></dt> <dd><p id="index-0">Returns the number of objects in sequence <em>o</em> on success, and <code class="docutils literal notranslate"><span class="pre">-1</span></code> on failure. This is 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.PySequence_Concat"> <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PySequence_Concat</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.PySequence_Concat" title="Permalink to this definition">¶</a></dt> <dd><em class="refcount">Return value: New reference.</em><p>Return the concatenation of <em>o1</em> and <em>o2</em> on success, and <em>NULL</em> on failure. This is the equivalent of the Python expression <code class="docutils literal notranslate"><span class="pre">o1</span> <span class="pre">+</span> <span class="pre">o2</span></code>.</p> </dd></dl> <dl class="function"> <dt id="c.PySequence_Repeat"> <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PySequence_Repeat</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em>, Py_ssize_t<em> count</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PySequence_Repeat" title="Permalink to this definition">¶</a></dt> <dd><em class="refcount">Return value: New reference.</em><p>Return the result of repeating sequence object <em>o</em> <em>count</em> times, or <em>NULL</em> on failure. This is the equivalent of the Python expression <code class="docutils literal notranslate"><span class="pre">o</span> <span class="pre">*</span> <span class="pre">count</span></code>.</p> <div class="versionchanged"> <p><span class="versionmodified">Changed in version 2.5: </span>This function used an <code class="xref c c-type docutils literal notranslate"><span class="pre">int</span></code> type for <em>count</em>. This might require changes in your code for properly supporting 64-bit systems.</p> </div> </dd></dl> <dl class="function"> <dt id="c.PySequence_InPlaceConcat"> <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PySequence_InPlaceConcat</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.PySequence_InPlaceConcat" title="Permalink to this definition">¶</a></dt> <dd><em class="refcount">Return value: New reference.</em><p>Return the concatenation of <em>o1</em> and <em>o2</em> on success, and <em>NULL</em> on failure. The operation is done <em>in-place</em> when <em>o1</em> supports it. This is the equivalent of the Python expression <code class="docutils literal notranslate"><span class="pre">o1</span> <span class="pre">+=</span> <span class="pre">o2</span></code>.</p> </dd></dl> <dl class="function"> <dt id="c.PySequence_InPlaceRepeat"> <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PySequence_InPlaceRepeat</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em>, Py_ssize_t<em> count</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PySequence_InPlaceRepeat" title="Permalink to this definition">¶</a></dt> <dd><em class="refcount">Return value: New reference.</em><p>Return the result of repeating sequence object <em>o</em> <em>count</em> times, or <em>NULL</em> on failure. The operation is done <em>in-place</em> when <em>o</em> supports it. This is the equivalent of the Python expression <code class="docutils literal notranslate"><span class="pre">o</span> <span class="pre">*=</span> <span class="pre">count</span></code>.</p> <div class="versionchanged"> <p><span class="versionmodified">Changed in version 2.5: </span>This function used an <code class="xref c c-type docutils literal notranslate"><span class="pre">int</span></code> type for <em>count</em>. This might require changes in your code for properly supporting 64-bit systems.</p> </div> </dd></dl> <dl class="function"> <dt id="c.PySequence_GetItem"> <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PySequence_GetItem</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em>, Py_ssize_t<em> i</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PySequence_GetItem" title="Permalink to this definition">¶</a></dt> <dd><em class="refcount">Return value: New reference.</em><p>Return the <em>i</em>th element of <em>o</em>, or <em>NULL</em> on failure. This is the equivalent of the Python expression <code class="docutils literal notranslate"><span class="pre">o[i]</span></code>.</p> <div class="versionchanged"> <p><span class="versionmodified">Changed in version 2.5: </span>This function used an <code class="xref c c-type docutils literal notranslate"><span class="pre">int</span></code> type for <em>i</em>. This might require changes in your code for properly supporting 64-bit systems.</p> </div> </dd></dl> <dl class="function"> <dt id="c.PySequence_GetSlice"> <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PySequence_GetSlice</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em>, Py_ssize_t<em> i1</em>, Py_ssize_t<em> i2</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PySequence_GetSlice" title="Permalink to this definition">¶</a></dt> <dd><em class="refcount">Return value: New reference.</em><p>Return the slice of sequence object <em>o</em> between <em>i1</em> and <em>i2</em>, or <em>NULL</em> on failure. This is the equivalent of the Python expression <code class="docutils literal notranslate"><span class="pre">o[i1:i2]</span></code>.</p> <div class="versionchanged"> <p><span class="versionmodified">Changed in version 2.5: </span>This function used an <code class="xref c c-type docutils literal notranslate"><span class="pre">int</span></code> type for <em>i1</em> and <em>i2</em>. This might require changes in your code for properly supporting 64-bit systems.</p> </div> </dd></dl> <dl class="function"> <dt id="c.PySequence_SetItem"> int <code class="descname">PySequence_SetItem</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em>, Py_ssize_t<em> i</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.PySequence_SetItem" title="Permalink to this definition">¶</a></dt> <dd><p>Assign object <em>v</em> to the <em>i</em>th element of <em>o</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[i]</span> <span class="pre">=</span> <span class="pre">v</span></code>. This function <em>does not</em> steal a reference to <em>v</em>.</p> <p>If <em>v</em> is <em>NULL</em>, the element is deleted, however this feature is deprecated in favour of using <a class="reference internal" href="#c.PySequence_DelItem" title="PySequence_DelItem"><code class="xref c c-func docutils literal notranslate"><span class="pre">PySequence_DelItem()</span></code></a>.</p> <div class="versionchanged"> <p><span class="versionmodified">Changed in version 2.5: </span>This function used an <code class="xref c c-type docutils literal notranslate"><span class="pre">int</span></code> type for <em>i</em>. This might require changes in your code for properly supporting 64-bit systems.</p> </div> </dd></dl> <dl class="function"> <dt id="c.PySequence_DelItem"> int <code class="descname">PySequence_DelItem</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em>, Py_ssize_t<em> i</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PySequence_DelItem" title="Permalink to this definition">¶</a></dt> <dd><p>Delete the <em>i</em>th element of 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[i]</span></code>.</p> <div class="versionchanged"> <p><span class="versionmodified">Changed in version 2.5: </span>This function used an <code class="xref c c-type docutils literal notranslate"><span class="pre">int</span></code> type for <em>i</em>. This might require changes in your code for properly supporting 64-bit systems.</p> </div> </dd></dl> <dl class="function"> <dt id="c.PySequence_SetSlice"> int <code class="descname">PySequence_SetSlice</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em>, Py_ssize_t<em> i1</em>, Py_ssize_t<em> i2</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.PySequence_SetSlice" title="Permalink to this definition">¶</a></dt> <dd><p>Assign the sequence object <em>v</em> to the slice in sequence object <em>o</em> from <em>i1</em> to <em>i2</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[i1:i2]</span> <span class="pre">=</span> <span class="pre">v</span></code>.</p> <p>If <em>v</em> is <em>NULL</em>, the slice is deleted, however this feature is deprecated in favour of using <a class="reference internal" href="#c.PySequence_DelSlice" title="PySequence_DelSlice"><code class="xref c c-func docutils literal notranslate"><span class="pre">PySequence_DelSlice()</span></code></a>.</p> <div class="versionchanged"> <p><span class="versionmodified">Changed in version 2.5: </span>This function used an <code class="xref c c-type docutils literal notranslate"><span class="pre">int</span></code> type for <em>i1</em> and <em>i2</em>. This might require changes in your code for properly supporting 64-bit systems.</p> </div> </dd></dl> <dl class="function"> <dt id="c.PySequence_DelSlice"> int <code class="descname">PySequence_DelSlice</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em>, Py_ssize_t<em> i1</em>, Py_ssize_t<em> i2</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PySequence_DelSlice" title="Permalink to this definition">¶</a></dt> <dd><p>Delete the slice in sequence object <em>o</em> from <em>i1</em> to <em>i2</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[i1:i2]</span></code>.</p> <div class="versionchanged"> <p><span class="versionmodified">Changed in version 2.5: </span>This function used an <code class="xref c c-type docutils literal notranslate"><span class="pre">int</span></code> type for <em>i1</em> and <em>i2</em>. This might require changes in your code for properly supporting 64-bit systems.</p> </div> </dd></dl> <dl class="function"> <dt id="c.PySequence_Count"> Py_ssize_t <code class="descname">PySequence_Count</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> *value</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PySequence_Count" title="Permalink to this definition">¶</a></dt> <dd><p>Return the number of occurrences of <em>value</em> in <em>o</em>, that is, return the number of keys for which <code class="docutils literal notranslate"><span class="pre">o[key]</span> <span class="pre">==</span> <span class="pre">value</span></code>. On failure, return <code class="docutils literal notranslate"><span class="pre">-1</span></code>. This is equivalent to the Python expression <code class="docutils literal notranslate"><span class="pre">o.count(value)</span></code>.</p> <div class="versionchanged"> <p><span class="versionmodified">Changed in version 2.5: </span>This function 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.PySequence_Contains"> int <code class="descname">PySequence_Contains</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> *value</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PySequence_Contains" title="Permalink to this definition">¶</a></dt> <dd><p>Determine if <em>o</em> contains <em>value</em>. If an item in <em>o</em> is equal to <em>value</em>, return <code class="docutils literal notranslate"><span class="pre">1</span></code>, otherwise return <code class="docutils literal notranslate"><span class="pre">0</span></code>. On error, return <code class="docutils literal notranslate"><span class="pre">-1</span></code>. This is equivalent to the Python expression <code class="docutils literal notranslate"><span class="pre">value</span> <span class="pre">in</span> <span class="pre">o</span></code>.</p> </dd></dl> <dl class="function"> <dt id="c.PySequence_Index"> Py_ssize_t <code class="descname">PySequence_Index</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> *value</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PySequence_Index" title="Permalink to this definition">¶</a></dt> <dd><p>Return the first index <em>i</em> for which <code class="docutils literal notranslate"><span class="pre">o[i]</span> <span class="pre">==</span> <span class="pre">value</span></code>. On error, return <code class="docutils literal notranslate"><span class="pre">-1</span></code>. This is equivalent to the Python expression <code class="docutils literal notranslate"><span class="pre">o.index(value)</span></code>.</p> <div class="versionchanged"> <p><span class="versionmodified">Changed in version 2.5: </span>This function 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.PySequence_List"> <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PySequence_List</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.PySequence_List" title="Permalink to this definition">¶</a></dt> <dd><em class="refcount">Return value: New reference.</em><p>Return a list object with the same contents as the arbitrary sequence <em>o</em>. The returned list is guaranteed to be new.</p> </dd></dl> <dl class="function"> <dt id="c.PySequence_Tuple"> <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PySequence_Tuple</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.PySequence_Tuple" title="Permalink to this definition">¶</a></dt> <dd><em class="refcount">Return value: New reference.</em><p id="index-1">Return a tuple object with the same contents as the arbitrary sequence <em>o</em> or <em>NULL</em> on failure. If <em>o</em> is a tuple, a new reference will be returned, otherwise a tuple will be constructed with the appropriate contents. This is equivalent to the Python expression <code class="docutils literal notranslate"><span class="pre">tuple(o)</span></code>.</p> </dd></dl> <dl class="function"> <dt id="c.PySequence_Fast"> <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PySequence_Fast</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> *m</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PySequence_Fast" title="Permalink to this definition">¶</a></dt> <dd><em class="refcount">Return value: New reference.</em><p>Return the sequence <em>o</em> as a list, unless it is already a tuple or list, in which case <em>o</em> is returned. Use <a class="reference internal" href="#c.PySequence_Fast_GET_ITEM" title="PySequence_Fast_GET_ITEM"><code class="xref c c-func docutils literal notranslate"><span class="pre">PySequence_Fast_GET_ITEM()</span></code></a> to access the members of the result. Returns <em>NULL</em> on failure. If the object is not a sequence, 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> with <em>m</em> as the message text.</p> </dd></dl> <dl class="function"> <dt id="c.PySequence_Fast_GET_ITEM"> <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PySequence_Fast_GET_ITEM</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em>, Py_ssize_t<em> i</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PySequence_Fast_GET_ITEM" title="Permalink to this definition">¶</a></dt> <dd><em class="refcount">Return value: Borrowed reference.</em><p>Return the <em>i</em>th element of <em>o</em>, assuming that <em>o</em> was returned by <a class="reference internal" href="#c.PySequence_Fast" title="PySequence_Fast"><code class="xref c c-func docutils literal notranslate"><span class="pre">PySequence_Fast()</span></code></a>, <em>o</em> is not <em>NULL</em>, and that <em>i</em> is within bounds.</p> <div class="versionchanged"> <p><span class="versionmodified">Changed in version 2.5: </span>This function used an <code class="xref c c-type docutils literal notranslate"><span class="pre">int</span></code> type for <em>i</em>. This might require changes in your code for properly supporting 64-bit systems.</p> </div> </dd></dl> <dl class="function"> <dt id="c.PySequence_Fast_ITEMS"> <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>** <code class="descname">PySequence_Fast_ITEMS</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.PySequence_Fast_ITEMS" title="Permalink to this definition">¶</a></dt> <dd><p>Return the underlying array of PyObject pointers. Assumes that <em>o</em> was returned by <a class="reference internal" href="#c.PySequence_Fast" title="PySequence_Fast"><code class="xref c c-func docutils literal notranslate"><span class="pre">PySequence_Fast()</span></code></a> and <em>o</em> is not <em>NULL</em>.</p> <p>Note, if a list gets resized, the reallocation may relocate the items array. So, only use the underlying array pointer in contexts where the sequence cannot change.</p> <div class="versionadded"> <p><span class="versionmodified">New in version 2.4.</span></p> </div> </dd></dl> <dl class="function"> <dt id="c.PySequence_ITEM"> <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PySequence_ITEM</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *o</em>, Py_ssize_t<em> i</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PySequence_ITEM" title="Permalink to this definition">¶</a></dt> <dd><em class="refcount">Return value: New reference.</em><p>Return the <em>i</em>th element of <em>o</em> or <em>NULL</em> on failure. Macro form of <a class="reference internal" href="#c.PySequence_GetItem" title="PySequence_GetItem"><code class="xref c c-func docutils literal notranslate"><span class="pre">PySequence_GetItem()</span></code></a> but without checking that <a class="reference internal" href="#c.PySequence_Check" title="PySequence_Check"><code class="xref c c-func docutils literal notranslate"><span class="pre">PySequence_Check()</span></code></a> on <em>o</em> is true and without adjustment for negative indices.</p> <div class="versionadded"> <p><span class="versionmodified">New in version 2.3.</span></p> </div> <div class="versionchanged"> <p><span class="versionmodified">Changed in version 2.5: </span>This function used an <code class="xref c c-type docutils literal notranslate"><span class="pre">int</span></code> type for <em>i</em>. This might require changes in your code for properly supporting 64-bit systems.</p> </div> </dd></dl> <dl class="function"> <dt id="c.PySequence_Fast_GET_SIZE"> Py_ssize_t <code class="descname">PySequence_Fast_GET_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.PySequence_Fast_GET_SIZE" title="Permalink to this definition">¶</a></dt> <dd><p>Returns the length of <em>o</em>, assuming that <em>o</em> was returned by <a class="reference internal" href="#c.PySequence_Fast" title="PySequence_Fast"><code class="xref c c-func docutils literal notranslate"><span class="pre">PySequence_Fast()</span></code></a> and that <em>o</em> is not <em>NULL</em>. The size can also be gotten by calling <a class="reference internal" href="#c.PySequence_Size" title="PySequence_Size"><code class="xref c c-func docutils literal notranslate"><span class="pre">PySequence_Size()</span></code></a> on <em>o</em>, but <a class="reference internal" href="#c.PySequence_Fast_GET_SIZE" title="PySequence_Fast_GET_SIZE"><code class="xref c c-func docutils literal notranslate"><span class="pre">PySequence_Fast_GET_SIZE()</span></code></a> is faster because it can assume <em>o</em> is a list or tuple.</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="number.html" title="previous chapter">Number Protocol</a></p> <h4>Next topic</h4> <p class="topless"><a href="mapping.html" title="next chapter">Mapping 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/sequence.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="mapping.html" title="Mapping Protocol" >next</a> |</li> <li class="right" > <a href="number.html" title="Number Protocol" >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 2.7.16 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> 1990-2019, 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 Mar 27, 2019. <a href="../bugs.html">Found a bug</a>? <br /> Created using <a href="http://sphinx.pocoo.org/">Sphinx</a> 1.7.6. </div> </body> </html>