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<div class="section" id="slice-objects">
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<span id="id1"></span><h1>Slice Objects<a class="headerlink" href="#slice-objects" title="Permalink to this headline">¶</a></h1>
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<dl class="var">
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<dt id="c.PySlice_Type">
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<a class="reference internal" href="type.html#c.PyTypeObject" title="PyTypeObject">PyTypeObject</a> <code class="descname">PySlice_Type</code><a class="headerlink" href="#c.PySlice_Type" title="Permalink to this definition">¶</a></dt>
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<dd><p>The type object for slice objects. This is the same as <a class="reference internal" href="../library/functions.html#slice" title="slice"><code class="xref py py-class docutils literal notranslate"><span class="pre">slice</span></code></a> in the
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Python layer.</p>
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</dd></dl>
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<dl class="function">
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<dt id="c.PySlice_Check">
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int <code class="descname">PySlice_Check</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *ob</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PySlice_Check" title="Permalink to this definition">¶</a></dt>
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<dd><p>Return true if <em>ob</em> is a slice object; <em>ob</em> must not be <em>NULL</em>.</p>
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</dd></dl>
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<dl class="function">
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<dt id="c.PySlice_New">
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<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PySlice_New</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *start</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *stop</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *step</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PySlice_New" title="Permalink to this definition">¶</a></dt>
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<dd><em class="refcount">Return value: New reference.</em><p>Return a new slice object with the given values. The <em>start</em>, <em>stop</em>, and
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<em>step</em> parameters are used as the values of the slice object attributes of
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the same names. Any of the values may be <em>NULL</em>, in which case the
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<code class="docutils literal notranslate"><span class="pre">None</span></code> will be used for the corresponding attribute. Return <em>NULL</em> if
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the new object could not be allocated.</p>
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</dd></dl>
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<dl class="function">
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<dt id="c.PySlice_GetIndices">
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int <code class="descname">PySlice_GetIndices</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *slice</em>, Py_ssize_t<em> length</em>, Py_ssize_t<em> *start</em>, Py_ssize_t<em> *stop</em>, Py_ssize_t<em> *step</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PySlice_GetIndices" title="Permalink to this definition">¶</a></dt>
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<dd><p>Retrieve the start, stop and step indices from the slice object <em>slice</em>,
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assuming a sequence of length <em>length</em>. Treats indices greater than
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<em>length</em> as errors.</p>
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<p>Returns <code class="docutils literal notranslate"><span class="pre">0</span></code> on success and <code class="docutils literal notranslate"><span class="pre">-1</span></code> on error with no exception set (unless one of
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the indices was not <a class="reference internal" href="../library/constants.html#None" title="None"><code class="xref py py-const docutils literal notranslate"><span class="pre">None</span></code></a> and failed to be converted to an integer,
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in which case <code class="docutils literal notranslate"><span class="pre">-1</span></code> is returned with an exception set).</p>
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<p>You probably do not want to use this function.</p>
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<div class="versionchanged">
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<p><span class="versionmodified changed">Changed in version 3.2: </span>The parameter type for the <em>slice</em> parameter was <code class="docutils literal notranslate"><span class="pre">PySliceObject*</span></code>
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before.</p>
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</div>
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</dd></dl>
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<dl class="function">
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<dt id="c.PySlice_GetIndicesEx">
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int <code class="descname">PySlice_GetIndicesEx</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *slice</em>, Py_ssize_t<em> length</em>, Py_ssize_t<em> *start</em>, Py_ssize_t<em> *stop</em>, Py_ssize_t<em> *step</em>, Py_ssize_t<em> *slicelength</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PySlice_GetIndicesEx" title="Permalink to this definition">¶</a></dt>
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<dd><p>Usable replacement for <a class="reference internal" href="#c.PySlice_GetIndices" title="PySlice_GetIndices"><code class="xref c c-func docutils literal notranslate"><span class="pre">PySlice_GetIndices()</span></code></a>. Retrieve the start,
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stop, and step indices from the slice object <em>slice</em> assuming a sequence of
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length <em>length</em>, and store the length of the slice in <em>slicelength</em>. Out
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of bounds indices are clipped in a manner consistent with the handling of
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normal slices.</p>
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<p>Returns <code class="docutils literal notranslate"><span class="pre">0</span></code> on success and <code class="docutils literal notranslate"><span class="pre">-1</span></code> on error with exception set.</p>
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<div class="admonition note">
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<p class="admonition-title">Note</p>
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<p>This function is considered not safe for resizable sequences.
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Its invocation should be replaced by a combination of
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<a class="reference internal" href="#c.PySlice_Unpack" title="PySlice_Unpack"><code class="xref c c-func docutils literal notranslate"><span class="pre">PySlice_Unpack()</span></code></a> and <a class="reference internal" href="#c.PySlice_AdjustIndices" title="PySlice_AdjustIndices"><code class="xref c c-func docutils literal notranslate"><span class="pre">PySlice_AdjustIndices()</span></code></a> where</p>
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<div class="highlight-c notranslate"><div class="highlight"><pre><span></span><span class="k">if</span> <span class="p">(</span><span class="n">PySlice_GetIndicesEx</span><span class="p">(</span><span class="n">slice</span><span class="p">,</span> <span class="n">length</span><span class="p">,</span> <span class="o">&</span><span class="n">start</span><span class="p">,</span> <span class="o">&</span><span class="n">stop</span><span class="p">,</span> <span class="o">&</span><span class="n">step</span><span class="p">,</span> <span class="o">&</span><span class="n">slicelength</span><span class="p">)</span> <span class="o"><</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
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<span class="c1">// return error</span>
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<span class="p">}</span>
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</pre></div>
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</div>
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<p>is replaced by</p>
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<div class="highlight-c notranslate"><div class="highlight"><pre><span></span><span class="k">if</span> <span class="p">(</span><span class="n">PySlice_Unpack</span><span class="p">(</span><span class="n">slice</span><span class="p">,</span> <span class="o">&</span><span class="n">start</span><span class="p">,</span> <span class="o">&</span><span class="n">stop</span><span class="p">,</span> <span class="o">&</span><span class="n">step</span><span class="p">)</span> <span class="o"><</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span>
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<span class="c1">// return error</span>
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<span class="p">}</span>
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<span class="n">slicelength</span> <span class="o">=</span> <span class="n">PySlice_AdjustIndices</span><span class="p">(</span><span class="n">length</span><span class="p">,</span> <span class="o">&</span><span class="n">start</span><span class="p">,</span> <span class="o">&</span><span class="n">stop</span><span class="p">,</span> <span class="n">step</span><span class="p">);</span>
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</pre></div>
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||
</div>
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||
</div>
|
||
<div class="versionchanged">
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||
<p><span class="versionmodified changed">Changed in version 3.2: </span>The parameter type for the <em>slice</em> parameter was <code class="docutils literal notranslate"><span class="pre">PySliceObject*</span></code>
|
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before.</p>
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||
</div>
|
||
<div class="versionchanged">
|
||
<p><span class="versionmodified changed">Changed in version 3.6.1: </span>If <code class="docutils literal notranslate"><span class="pre">Py_LIMITED_API</span></code> is not set or set to the value between <code class="docutils literal notranslate"><span class="pre">0x03050400</span></code>
|
||
and <code class="docutils literal notranslate"><span class="pre">0x03060000</span></code> (not including) or <code class="docutils literal notranslate"><span class="pre">0x03060100</span></code> or higher
|
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<code class="xref c c-func docutils literal notranslate"><span class="pre">PySlice_GetIndicesEx()</span></code> is implemented as a macro using
|
||
<code class="xref c c-func docutils literal notranslate"><span class="pre">PySlice_Unpack()</span></code> and <code class="xref c c-func docutils literal notranslate"><span class="pre">PySlice_AdjustIndices()</span></code>.
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Arguments <em>start</em>, <em>stop</em> and <em>step</em> are evaluated more than once.</p>
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</div>
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<div class="deprecated">
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<p><span class="versionmodified deprecated">Deprecated since version 3.6.1: </span>If <code class="docutils literal notranslate"><span class="pre">Py_LIMITED_API</span></code> is set to the value less than <code class="docutils literal notranslate"><span class="pre">0x03050400</span></code> or
|
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between <code class="docutils literal notranslate"><span class="pre">0x03060000</span></code> and <code class="docutils literal notranslate"><span class="pre">0x03060100</span></code> (not including)
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<code class="xref c c-func docutils literal notranslate"><span class="pre">PySlice_GetIndicesEx()</span></code> is a deprecated function.</p>
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</div>
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</dd></dl>
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<dl class="function">
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<dt id="c.PySlice_Unpack">
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int <code class="descname">PySlice_Unpack</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *slice</em>, Py_ssize_t<em> *start</em>, Py_ssize_t<em> *stop</em>, Py_ssize_t<em> *step</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PySlice_Unpack" title="Permalink to this definition">¶</a></dt>
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<dd><p>Extract the start, stop and step data members from a slice object as
|
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C integers. Silently reduce values larger than <code class="docutils literal notranslate"><span class="pre">PY_SSIZE_T_MAX</span></code> to
|
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<code class="docutils literal notranslate"><span class="pre">PY_SSIZE_T_MAX</span></code>, silently boost the start and stop values less than
|
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<code class="docutils literal notranslate"><span class="pre">PY_SSIZE_T_MIN</span></code> to <code class="docutils literal notranslate"><span class="pre">PY_SSIZE_T_MIN</span></code>, and silently boost the step
|
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values less than <code class="docutils literal notranslate"><span class="pre">-PY_SSIZE_T_MAX</span></code> to <code class="docutils literal notranslate"><span class="pre">-PY_SSIZE_T_MAX</span></code>.</p>
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<p>Return <code class="docutils literal notranslate"><span class="pre">-1</span></code> on error, <code class="docutils literal notranslate"><span class="pre">0</span></code> on success.</p>
|
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<div class="versionadded">
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<p><span class="versionmodified added">New in version 3.6.1.</span></p>
|
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</div>
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</dd></dl>
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|
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<dl class="function">
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<dt id="c.PySlice_AdjustIndices">
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Py_ssize_t <code class="descname">PySlice_AdjustIndices</code><span class="sig-paren">(</span>Py_ssize_t<em> length</em>, Py_ssize_t<em> *start</em>, Py_ssize_t<em> *stop</em>, Py_ssize_t<em> step</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PySlice_AdjustIndices" title="Permalink to this definition">¶</a></dt>
|
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<dd><p>Adjust start/end slice indices assuming a sequence of the specified length.
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Out of bounds indices are clipped in a manner consistent with the handling
|
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of normal slices.</p>
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<p>Return the length of the slice. Always successful. Doesn’t call Python
|
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code.</p>
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<div class="versionadded">
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<p><span class="versionmodified added">New in version 3.6.1.</span></p>
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</div>
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</dd></dl>
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<div class="section" id="ellipsis-object">
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<h1>Ellipsis Object<a class="headerlink" href="#ellipsis-object" title="Permalink to this headline">¶</a></h1>
|
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<dl class="var">
|
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<dt id="c.Py_Ellipsis">
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<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a> *<code class="descname">Py_Ellipsis</code><a class="headerlink" href="#c.Py_Ellipsis" title="Permalink to this definition">¶</a></dt>
|
||
<dd><p>The Python <code class="docutils literal notranslate"><span class="pre">Ellipsis</span></code> object. This object has no methods. It needs to be
|
||
treated just like any other object with respect to reference counts. Like
|
||
<a class="reference internal" href="none.html#c.Py_None" title="Py_None"><code class="xref c c-data docutils literal notranslate"><span class="pre">Py_None</span></code></a> it is a singleton object.</p>
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<ul>
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<li><a class="reference internal" href="#">Slice Objects</a></li>
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<li><a class="reference internal" href="#ellipsis-object">Ellipsis Object</a></li>
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© <a href="../copyright.html">Copyright</a> 2001-2019, Python Software Foundation.
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Last updated on Jul 13, 2019.
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Created using <a href="http://sphinx.pocoo.org/">Sphinx</a> 2.0.1.
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