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The first, a sequence iterator, works with an arbitrary sequence supporting the <code class="xref py py-meth docutils literal notranslate"><span class="pre">__getitem__()</span></code> method. The second works with a callable object and a sentinel value, calling the callable for each item in the sequence, and ending the iteration when the sentinel value is returned.</p> <dl class="c var"> <dt class="sig sig-object c" id="c.PySeqIter_Type"> <a class="reference internal" href="type.html#c.PyTypeObject" title="PyTypeObject"><span class="n"><span class="pre">PyTypeObject</span></span></a><span class="w"> </span><span class="sig-name descname"><span class="n"><span class="pre">PySeqIter_Type</span></span></span><a class="headerlink" href="#c.PySeqIter_Type" title="Permalink to this definition">¶</a><br /></dt> <dd><em class="stableabi"> Part of the <a class="reference internal" href="stable.html#stable"><span class="std std-ref">Stable ABI</span></a>.</em><p>Type object for iterator objects returned by <a class="reference internal" href="#c.PySeqIter_New" title="PySeqIter_New"><code class="xref c c-func docutils literal notranslate"><span class="pre">PySeqIter_New()</span></code></a> and the one-argument form of the <a class="reference internal" href="../library/functions.html#iter" title="iter"><code class="xref py py-func docutils literal notranslate"><span class="pre">iter()</span></code></a> built-in function for built-in sequence types.</p> </dd></dl> <dl class="c function"> <dt class="sig sig-object c" id="c.PySeqIter_Check"> <span class="kt"><span class="pre">int</span></span><span class="w"> </span><span class="sig-name descname"><span class="n"><span class="pre">PySeqIter_Check</span></span></span><span class="sig-paren">(</span><span class="n"><span class="pre">op</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PySeqIter_Check" title="Permalink to this definition">¶</a><br /></dt> <dd><p>Return true if the type of <em>op</em> is <a class="reference internal" href="#c.PySeqIter_Type" title="PySeqIter_Type"><code class="xref c c-data docutils literal notranslate"><span class="pre">PySeqIter_Type</span></code></a>. This function always succeeds.</p> </dd></dl> <dl class="c function"> <dt class="sig sig-object c" id="c.PySeqIter_New"> <a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><span class="n"><span class="pre">PyObject</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="sig-name descname"><span class="n"><span class="pre">PySeqIter_New</span></span></span><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><span class="n"><span class="pre">PyObject</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="n"><span class="pre">seq</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PySeqIter_New" title="Permalink to this definition">¶</a><br /></dt> <dd><em class="refcount">Return value: New reference.</em><em class="stableabi"> Part of the <a class="reference internal" href="stable.html#stable"><span class="std std-ref">Stable ABI</span></a>.</em><p>Return an iterator that works with a general sequence object, <em>seq</em>. The iteration ends when the sequence raises <a class="reference internal" href="../library/exceptions.html#IndexError" title="IndexError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">IndexError</span></code></a> for the subscripting operation.</p> </dd></dl> <dl class="c var"> <dt class="sig sig-object c" id="c.PyCallIter_Type"> <a class="reference internal" href="type.html#c.PyTypeObject" title="PyTypeObject"><span class="n"><span class="pre">PyTypeObject</span></span></a><span class="w"> </span><span class="sig-name descname"><span class="n"><span class="pre">PyCallIter_Type</span></span></span><a class="headerlink" href="#c.PyCallIter_Type" title="Permalink to this definition">¶</a><br /></dt> <dd><em class="stableabi"> Part of the <a class="reference internal" href="stable.html#stable"><span class="std std-ref">Stable ABI</span></a>.</em><p>Type object for iterator objects returned by <a class="reference internal" href="#c.PyCallIter_New" title="PyCallIter_New"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyCallIter_New()</span></code></a> and the two-argument form of the <a class="reference internal" href="../library/functions.html#iter" title="iter"><code class="xref py py-func docutils literal notranslate"><span class="pre">iter()</span></code></a> built-in function.</p> </dd></dl> <dl class="c function"> <dt class="sig sig-object c" id="c.PyCallIter_Check"> <span class="kt"><span class="pre">int</span></span><span class="w"> </span><span class="sig-name descname"><span class="n"><span class="pre">PyCallIter_Check</span></span></span><span class="sig-paren">(</span><span class="n"><span class="pre">op</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyCallIter_Check" title="Permalink to this definition">¶</a><br /></dt> <dd><p>Return true if the type of <em>op</em> is <a class="reference internal" href="#c.PyCallIter_Type" title="PyCallIter_Type"><code class="xref c c-data docutils literal notranslate"><span class="pre">PyCallIter_Type</span></code></a>. This function always succeeds.</p> </dd></dl> <dl class="c function"> <dt class="sig sig-object c" id="c.PyCallIter_New"> <a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><span class="n"><span class="pre">PyObject</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="sig-name descname"><span class="n"><span class="pre">PyCallIter_New</span></span></span><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><span class="n"><span class="pre">PyObject</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="n"><span class="pre">callable</span></span>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><span class="n"><span class="pre">PyObject</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="n"><span class="pre">sentinel</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyCallIter_New" title="Permalink to this definition">¶</a><br /></dt> <dd><em class="refcount">Return value: New reference.</em><em class="stableabi"> Part of the <a class="reference internal" href="stable.html#stable"><span class="std std-ref">Stable ABI</span></a>.</em><p>Return a new iterator. The first parameter, <em>callable</em>, can be any Python callable object that can be called with no parameters; each call to it should return the next item in the iteration. When <em>callable</em> returns a value equal to <em>sentinel</em>, the iteration will be terminated.</p> </dd></dl> </section> <div class="clearer"></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="module.html" title="previous chapter">Module Objects</a></p> <h4>Next topic</h4> <p class="topless"><a href="descriptor.html" title="next chapter">Descriptor Objects</a></p> <div role="note" aria-label="source link"> <h3>This Page</h3> <ul class="this-page-menu"> <li><a href="../bugs.html">Report a Bug</a></li> <li> <a href="https://github.com/python/cpython/blob/3.10/Doc/c-api/iterator.rst" rel="nofollow">Show Source </a> </li> </ul> </div> </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="descriptor.html" title="Descriptor Objects" >next</a> |</li> <li class="right" > <a href="module.html" title="Module Objects" >previous</a> |</li> <li><img src="../_static/py.svg" alt="python logo" style="vertical-align: middle; margin-top: -1px"/></li> <li><a href="https://www.python.org/">Python</a> »</li> <li class="switchers"> <div class="language_switcher_placeholder"></div> <div class="version_switcher_placeholder"></div> </li> <li> </li> <li id="cpython-language-and-version"> <a href="../index.html">3.10.12 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="concrete.html" >Concrete Objects Layer</a> »</li> <li class="nav-item nav-item-this"><a href="">Iterator Objects</a></li> <li class="right"> <div class="inline-search" role="search"> <form class="inline-search" action="../search.html" method="get"> <input placeholder="Quick search" aria-label="Quick search" 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> | </li> </ul> </div> <div class="footer"> © <a href="../copyright.html">Copyright</a> 2001-2025, Python Software Foundation. <br /> This page is licensed under the Python Software Foundation License Version 2. <br /> Examples, recipes, and other code in the documentation are additionally licensed under the Zero Clause BSD License. <br /> See <a href="/license.html">History and License</a> for more information.<br /> <br /> The Python Software Foundation is a non-profit corporation. <a href="https://www.python.org/psf/donations/">Please donate.</a> <br /> <br /> Last updated on February 04, 2025. <a href="/bugs.html">Found a bug</a>? <br /> Created using <a href="https://www.sphinx-doc.org/">Sphinx</a> 4.3.2. </div> </body> </html> Save