Edit File: dict.html
<!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="Content-Type" content="text/html; charset=utf-8" /> <title>Dictionary Objects — Python 2.7.5 documentation</title> <link rel="stylesheet" href="../_static/default.css" type="text/css" /> <link rel="stylesheet" href="../_static/pygments.css" type="text/css" /> <script type="text/javascript"> var DOCUMENTATION_OPTIONS = { URL_ROOT: '../', VERSION: '2.7.5', COLLAPSE_INDEX: false, FILE_SUFFIX: '.html', HAS_SOURCE: true }; </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 2.7.5 documentation" href="../_static/opensearch.xml"/> <link rel="author" title="About these documents" href="../about.html" /> <link rel="copyright" title="Copyright" href="../copyright.html" /> <link rel="top" title="Python 2.7.5 documentation" href="../index.html" /> <link rel="up" title="Concrete Objects Layer" href="concrete.html" /> <link rel="next" title="Class and Instance Objects" href="class.html" /> <link rel="prev" title="List Objects" href="list.html" /> <link rel="shortcut icon" type="image/png" href="../_static/py.png" /> <script type="text/javascript" src="../_static/copybutton.js"></script> </head> <body> <div class="related"> <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="class.html" title="Class and Instance Objects" accesskey="N">next</a> |</li> <li class="right" > <a href="list.html" title="List Objects" accesskey="P">previous</a> |</li> <li><img src="../_static/py.png" alt="" style="vertical-align: middle; margin-top: -1px"/></li> <li><a href="http://www.python.org/">Python</a> »</li> <li> <a href="../index.html">Python 2.7.5 documentation</a> » </li> <li><a href="index.html" >Python/C API Reference Manual</a> »</li> <li><a href="concrete.html" accesskey="U">Concrete Objects Layer</a> »</li> </ul> </div> <div class="document"> <div class="documentwrapper"> <div class="bodywrapper"> <div class="body"> <div class="section" id="dictionary-objects"> <span id="dictobjects"></span><h1>Dictionary Objects<a class="headerlink" href="#dictionary-objects" title="Permalink to this headline">¶</a></h1> <span class="target" id="index-0"></span><dl class="type"> <dt id="PyDictObject"> <tt class="descname">PyDictObject</tt><a class="headerlink" href="#PyDictObject" title="Permalink to this definition">¶</a></dt> <dd><p>This subtype of <a class="reference internal" href="structures.html#PyObject" title="PyObject"><tt class="xref c c-type docutils literal"><span class="pre">PyObject</span></tt></a> represents a Python dictionary object.</p> </dd></dl> <dl class="var"> <dt id="PyDict_Type"> <a class="reference internal" href="type.html#PyTypeObject" title="PyTypeObject">PyTypeObject</a> <tt class="descname">PyDict_Type</tt><a class="headerlink" href="#PyDict_Type" title="Permalink to this definition">¶</a></dt> <dd><p id="index-1">This instance of <a class="reference internal" href="type.html#PyTypeObject" title="PyTypeObject"><tt class="xref c c-type docutils literal"><span class="pre">PyTypeObject</span></tt></a> represents the Python dictionary type. This is exposed to Python programs as <tt class="docutils literal"><span class="pre">dict</span></tt> and <tt class="docutils literal"><span class="pre">types.DictType</span></tt>.</p> </dd></dl> <dl class="function"> <dt id="PyDict_Check"> int <tt class="descname">PyDict_Check</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *p</em><big>)</big><a class="headerlink" href="#PyDict_Check" title="Permalink to this definition">¶</a></dt> <dd><p>Return true if <em>p</em> is a dict object or an instance of a subtype of the dict type.</p> <p class="versionchanged"> <span class="versionmodified">Changed in version 2.2: </span>Allowed subtypes to be accepted.</p> </dd></dl> <dl class="function"> <dt id="PyDict_CheckExact"> int <tt class="descname">PyDict_CheckExact</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *p</em><big>)</big><a class="headerlink" href="#PyDict_CheckExact" title="Permalink to this definition">¶</a></dt> <dd><p>Return true if <em>p</em> is a dict object, but not an instance of a subtype of the dict type.</p> <p class="versionadded"> <span class="versionmodified">New in version 2.4.</span></p> </dd></dl> <dl class="function"> <dt id="PyDict_New"> <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a>* <tt class="descname">PyDict_New</tt><big>(</big><big>)</big><a class="headerlink" href="#PyDict_New" title="Permalink to this definition">¶</a></dt> <dd><em class="refcount">Return value: New reference.</em><p>Return a new empty dictionary, or <em>NULL</em> on failure.</p> </dd></dl> <dl class="function"> <dt id="PyDictProxy_New"> <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a>* <tt class="descname">PyDictProxy_New</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *dict</em><big>)</big><a class="headerlink" href="#PyDictProxy_New" title="Permalink to this definition">¶</a></dt> <dd><em class="refcount">Return value: New reference.</em><p>Return a proxy object for a mapping which enforces read-only behavior. This is normally used to create a proxy to prevent modification of the dictionary for non-dynamic class types.</p> <p class="versionadded"> <span class="versionmodified">New in version 2.2.</span></p> </dd></dl> <dl class="function"> <dt id="PyDict_Clear"> void <tt class="descname">PyDict_Clear</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *p</em><big>)</big><a class="headerlink" href="#PyDict_Clear" title="Permalink to this definition">¶</a></dt> <dd><p>Empty an existing dictionary of all key-value pairs.</p> </dd></dl> <dl class="function"> <dt id="PyDict_Contains"> int <tt class="descname">PyDict_Contains</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *p</em>, <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *key</em><big>)</big><a class="headerlink" href="#PyDict_Contains" title="Permalink to this definition">¶</a></dt> <dd><p>Determine if dictionary <em>p</em> contains <em>key</em>. If an item in <em>p</em> is matches <em>key</em>, return <tt class="docutils literal"><span class="pre">1</span></tt>, otherwise return <tt class="docutils literal"><span class="pre">0</span></tt>. On error, return <tt class="docutils literal"><span class="pre">-1</span></tt>. This is equivalent to the Python expression <tt class="docutils literal"><span class="pre">key</span> <span class="pre">in</span> <span class="pre">p</span></tt>.</p> <p class="versionadded"> <span class="versionmodified">New in version 2.4.</span></p> </dd></dl> <dl class="function"> <dt id="PyDict_Copy"> <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a>* <tt class="descname">PyDict_Copy</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *p</em><big>)</big><a class="headerlink" href="#PyDict_Copy" title="Permalink to this definition">¶</a></dt> <dd><em class="refcount">Return value: New reference.</em><p>Return a new dictionary that contains the same key-value pairs as <em>p</em>.</p> <p class="versionadded"> <span class="versionmodified">New in version 1.6.</span></p> </dd></dl> <dl class="function"> <dt id="PyDict_SetItem"> int <tt class="descname">PyDict_SetItem</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *p</em>, <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *key</em>, <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *val</em><big>)</big><a class="headerlink" href="#PyDict_SetItem" title="Permalink to this definition">¶</a></dt> <dd><p>Insert <em>value</em> into the dictionary <em>p</em> with a key of <em>key</em>. <em>key</em> must be <a class="reference internal" href="../glossary.html#term-hashable"><em class="xref std std-term">hashable</em></a>; if it isn’t, <a class="reference internal" href="../library/exceptions.html#exceptions.TypeError" title="exceptions.TypeError"><tt class="xref py py-exc docutils literal"><span class="pre">TypeError</span></tt></a> will be raised. Return <tt class="docutils literal"><span class="pre">0</span></tt> on success or <tt class="docutils literal"><span class="pre">-1</span></tt> on failure.</p> </dd></dl> <dl class="function"> <dt id="PyDict_SetItemString"> int <tt class="descname">PyDict_SetItemString</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *p</em>, const char<em> *key</em>, <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *val</em><big>)</big><a class="headerlink" href="#PyDict_SetItemString" title="Permalink to this definition">¶</a></dt> <dd><p id="index-2">Insert <em>value</em> into the dictionary <em>p</em> using <em>key</em> as a key. <em>key</em> should be a <tt class="xref c c-type docutils literal"><span class="pre">char*</span></tt>. The key object is created using <tt class="docutils literal"><span class="pre">PyString_FromString(key)</span></tt>. Return <tt class="docutils literal"><span class="pre">0</span></tt> on success or <tt class="docutils literal"><span class="pre">-1</span></tt> on failure.</p> </dd></dl> <dl class="function"> <dt id="PyDict_DelItem"> int <tt class="descname">PyDict_DelItem</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *p</em>, <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *key</em><big>)</big><a class="headerlink" href="#PyDict_DelItem" title="Permalink to this definition">¶</a></dt> <dd><p>Remove the entry in dictionary <em>p</em> with key <em>key</em>. <em>key</em> must be hashable; if it isn’t, <a class="reference internal" href="../library/exceptions.html#exceptions.TypeError" title="exceptions.TypeError"><tt class="xref py py-exc docutils literal"><span class="pre">TypeError</span></tt></a> is raised. Return <tt class="docutils literal"><span class="pre">0</span></tt> on success or <tt class="docutils literal"><span class="pre">-1</span></tt> on failure.</p> </dd></dl> <dl class="function"> <dt id="PyDict_DelItemString"> int <tt class="descname">PyDict_DelItemString</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *p</em>, char<em> *key</em><big>)</big><a class="headerlink" href="#PyDict_DelItemString" title="Permalink to this definition">¶</a></dt> <dd><p>Remove the entry in dictionary <em>p</em> which has a key specified by the string <em>key</em>. Return <tt class="docutils literal"><span class="pre">0</span></tt> on success or <tt class="docutils literal"><span class="pre">-1</span></tt> on failure.</p> </dd></dl> <dl class="function"> <dt id="PyDict_GetItem"> <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a>* <tt class="descname">PyDict_GetItem</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *p</em>, <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *key</em><big>)</big><a class="headerlink" href="#PyDict_GetItem" title="Permalink to this definition">¶</a></dt> <dd><em class="refcount">Return value: Borrowed reference.</em><p>Return the object from dictionary <em>p</em> which has a key <em>key</em>. Return <em>NULL</em> if the key <em>key</em> is not present, but <em>without</em> setting an exception.</p> </dd></dl> <dl class="function"> <dt id="PyDict_GetItemString"> <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a>* <tt class="descname">PyDict_GetItemString</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *p</em>, const char<em> *key</em><big>)</big><a class="headerlink" href="#PyDict_GetItemString" title="Permalink to this definition">¶</a></dt> <dd><em class="refcount">Return value: Borrowed reference.</em><p>This is the same as <a class="reference internal" href="#PyDict_GetItem" title="PyDict_GetItem"><tt class="xref c c-func docutils literal"><span class="pre">PyDict_GetItem()</span></tt></a>, but <em>key</em> is specified as a <tt class="xref c c-type docutils literal"><span class="pre">char*</span></tt>, rather than a <a class="reference internal" href="structures.html#PyObject" title="PyObject"><tt class="xref c c-type docutils literal"><span class="pre">PyObject*</span></tt></a>.</p> </dd></dl> <dl class="function"> <dt id="PyDict_Items"> <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a>* <tt class="descname">PyDict_Items</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *p</em><big>)</big><a class="headerlink" href="#PyDict_Items" title="Permalink to this definition">¶</a></dt> <dd><em class="refcount">Return value: New reference.</em><p>Return a <a class="reference internal" href="list.html#PyListObject" title="PyListObject"><tt class="xref c c-type docutils literal"><span class="pre">PyListObject</span></tt></a> containing all the items from the dictionary, as in the dictionary method <a class="reference internal" href="../library/stdtypes.html#dict.items" title="dict.items"><tt class="xref py py-meth docutils literal"><span class="pre">dict.items()</span></tt></a>.</p> </dd></dl> <dl class="function"> <dt id="PyDict_Keys"> <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a>* <tt class="descname">PyDict_Keys</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *p</em><big>)</big><a class="headerlink" href="#PyDict_Keys" title="Permalink to this definition">¶</a></dt> <dd><em class="refcount">Return value: New reference.</em><p>Return a <a class="reference internal" href="list.html#PyListObject" title="PyListObject"><tt class="xref c c-type docutils literal"><span class="pre">PyListObject</span></tt></a> containing all the keys from the dictionary, as in the dictionary method <a class="reference internal" href="../library/stdtypes.html#dict.keys" title="dict.keys"><tt class="xref py py-meth docutils literal"><span class="pre">dict.keys()</span></tt></a>.</p> </dd></dl> <dl class="function"> <dt id="PyDict_Values"> <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a>* <tt class="descname">PyDict_Values</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *p</em><big>)</big><a class="headerlink" href="#PyDict_Values" title="Permalink to this definition">¶</a></dt> <dd><em class="refcount">Return value: New reference.</em><p>Return a <a class="reference internal" href="list.html#PyListObject" title="PyListObject"><tt class="xref c c-type docutils literal"><span class="pre">PyListObject</span></tt></a> containing all the values from the dictionary <em>p</em>, as in the dictionary method <a class="reference internal" href="../library/stdtypes.html#dict.values" title="dict.values"><tt class="xref py py-meth docutils literal"><span class="pre">dict.values()</span></tt></a>.</p> </dd></dl> <dl class="function"> <dt id="PyDict_Size"> Py_ssize_t <tt class="descname">PyDict_Size</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *p</em><big>)</big><a class="headerlink" href="#PyDict_Size" title="Permalink to this definition">¶</a></dt> <dd><p id="index-3">Return the number of items in the dictionary. This is equivalent to <tt class="docutils literal"><span class="pre">len(p)</span></tt> on a dictionary.</p> <p class="versionchanged"> <span class="versionmodified">Changed in version 2.5: </span>This function returned an <tt class="xref c c-type docutils literal"><span class="pre">int</span></tt> type. This might require changes in your code for properly supporting 64-bit systems.</p> </dd></dl> <dl class="function"> <dt id="PyDict_Next"> int <tt class="descname">PyDict_Next</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *p</em>, Py_ssize_t<em> *ppos</em>, <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> **pkey</em>, <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> **pvalue</em><big>)</big><a class="headerlink" href="#PyDict_Next" title="Permalink to this definition">¶</a></dt> <dd><p>Iterate over all key-value pairs in the dictionary <em>p</em>. The <tt class="xref c c-type docutils literal"><span class="pre">Py_ssize_t</span></tt> referred to by <em>ppos</em> must be initialized to <tt class="docutils literal"><span class="pre">0</span></tt> prior to the first call to this function to start the iteration; the function returns true for each pair in the dictionary, and false once all pairs have been reported. The parameters <em>pkey</em> and <em>pvalue</em> should either point to <a class="reference internal" href="structures.html#PyObject" title="PyObject"><tt class="xref c c-type docutils literal"><span class="pre">PyObject*</span></tt></a> variables that will be filled in with each key and value, respectively, or may be <em>NULL</em>. Any references returned through them are borrowed. <em>ppos</em> should not be altered during iteration. Its value represents offsets within the internal dictionary structure, and since the structure is sparse, the offsets are not consecutive.</p> <p>For example:</p> <div class="highlight-c"><div class="highlight"><pre><span class="n">PyObject</span> <span class="o">*</span><span class="n">key</span><span class="p">,</span> <span class="o">*</span><span class="n">value</span><span class="p">;</span> <span class="n">Py_ssize_t</span> <span class="n">pos</span> <span class="o">=</span> <span class="mi">0</span><span class="p">;</span> <span class="k">while</span> <span class="p">(</span><span class="n">PyDict_Next</span><span class="p">(</span><span class="n">self</span><span class="o">-></span><span class="n">dict</span><span class="p">,</span> <span class="o">&</span><span class="n">pos</span><span class="p">,</span> <span class="o">&</span><span class="n">key</span><span class="p">,</span> <span class="o">&</span><span class="n">value</span><span class="p">))</span> <span class="p">{</span> <span class="cm">/* do something interesting with the values... */</span> <span class="p">...</span> <span class="p">}</span> </pre></div> </div> <p>The dictionary <em>p</em> should not be mutated during iteration. It is safe (since Python 2.1) to modify the values of the keys as you iterate over the dictionary, but only so long as the set of keys does not change. For example:</p> <div class="highlight-c"><div class="highlight"><pre><span class="n">PyObject</span> <span class="o">*</span><span class="n">key</span><span class="p">,</span> <span class="o">*</span><span class="n">value</span><span class="p">;</span> <span class="n">Py_ssize_t</span> <span class="n">pos</span> <span class="o">=</span> <span class="mi">0</span><span class="p">;</span> <span class="k">while</span> <span class="p">(</span><span class="n">PyDict_Next</span><span class="p">(</span><span class="n">self</span><span class="o">-></span><span class="n">dict</span><span class="p">,</span> <span class="o">&</span><span class="n">pos</span><span class="p">,</span> <span class="o">&</span><span class="n">key</span><span class="p">,</span> <span class="o">&</span><span class="n">value</span><span class="p">))</span> <span class="p">{</span> <span class="kt">int</span> <span class="n">i</span> <span class="o">=</span> <span class="n">PyInt_AS_LONG</span><span class="p">(</span><span class="n">value</span><span class="p">)</span> <span class="o">+</span> <span class="mi">1</span><span class="p">;</span> <span class="n">PyObject</span> <span class="o">*</span><span class="n">o</span> <span class="o">=</span> <span class="n">PyInt_FromLong</span><span class="p">(</span><span class="n">i</span><span class="p">);</span> <span class="k">if</span> <span class="p">(</span><span class="n">o</span> <span class="o">==</span> <span class="nb">NULL</span><span class="p">)</span> <span class="k">return</span> <span class="o">-</span><span class="mi">1</span><span class="p">;</span> <span class="k">if</span> <span class="p">(</span><span class="n">PyDict_SetItem</span><span class="p">(</span><span class="n">self</span><span class="o">-></span><span class="n">dict</span><span class="p">,</span> <span class="n">key</span><span class="p">,</span> <span class="n">o</span><span class="p">)</span> <span class="o"><</span> <span class="mi">0</span><span class="p">)</span> <span class="p">{</span> <span class="n">Py_DECREF</span><span class="p">(</span><span class="n">o</span><span class="p">);</span> <span class="k">return</span> <span class="o">-</span><span class="mi">1</span><span class="p">;</span> <span class="p">}</span> <span class="n">Py_DECREF</span><span class="p">(</span><span class="n">o</span><span class="p">);</span> <span class="p">}</span> </pre></div> </div> <p class="versionchanged"> <span class="versionmodified">Changed in version 2.5: </span>This function used an <tt class="xref c c-type docutils literal"><span class="pre">int</span> <span class="pre">*</span></tt> type for <em>ppos</em>. This might require changes in your code for properly supporting 64-bit systems.</p> </dd></dl> <dl class="function"> <dt id="PyDict_Merge"> int <tt class="descname">PyDict_Merge</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *a</em>, <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *b</em>, int<em> override</em><big>)</big><a class="headerlink" href="#PyDict_Merge" title="Permalink to this definition">¶</a></dt> <dd><p>Iterate over mapping object <em>b</em> adding key-value pairs to dictionary <em>a</em>. <em>b</em> may be a dictionary, or any object supporting <a class="reference internal" href="mapping.html#PyMapping_Keys" title="PyMapping_Keys"><tt class="xref c c-func docutils literal"><span class="pre">PyMapping_Keys()</span></tt></a> and <a class="reference internal" href="object.html#PyObject_GetItem" title="PyObject_GetItem"><tt class="xref c c-func docutils literal"><span class="pre">PyObject_GetItem()</span></tt></a>. If <em>override</em> is true, existing pairs in <em>a</em> will be replaced if a matching key is found in <em>b</em>, otherwise pairs will only be added if there is not a matching key in <em>a</em>. Return <tt class="docutils literal"><span class="pre">0</span></tt> on success or <tt class="docutils literal"><span class="pre">-1</span></tt> if an exception was raised.</p> <p class="versionadded"> <span class="versionmodified">New in version 2.2.</span></p> </dd></dl> <dl class="function"> <dt id="PyDict_Update"> int <tt class="descname">PyDict_Update</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *a</em>, <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *b</em><big>)</big><a class="headerlink" href="#PyDict_Update" title="Permalink to this definition">¶</a></dt> <dd><p>This is the same as <tt class="docutils literal"><span class="pre">PyDict_Merge(a,</span> <span class="pre">b,</span> <span class="pre">1)</span></tt> in C, or <tt class="docutils literal"><span class="pre">a.update(b)</span></tt> in Python. Return <tt class="docutils literal"><span class="pre">0</span></tt> on success or <tt class="docutils literal"><span class="pre">-1</span></tt> if an exception was raised.</p> <p class="versionadded"> <span class="versionmodified">New in version 2.2.</span></p> </dd></dl> <dl class="function"> <dt id="PyDict_MergeFromSeq2"> int <tt class="descname">PyDict_MergeFromSeq2</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *a</em>, <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *seq2</em>, int<em> override</em><big>)</big><a class="headerlink" href="#PyDict_MergeFromSeq2" title="Permalink to this definition">¶</a></dt> <dd><p>Update or merge into dictionary <em>a</em>, from the key-value pairs in <em>seq2</em>. <em>seq2</em> must be an iterable object producing iterable objects of length 2, viewed as key-value pairs. In case of duplicate keys, the last wins if <em>override</em> is true, else the first wins. Return <tt class="docutils literal"><span class="pre">0</span></tt> on success or <tt class="docutils literal"><span class="pre">-1</span></tt> if an exception was raised. Equivalent Python (except for the return value):</p> <div class="highlight-c"><div class="highlight"><pre><span class="n">def</span> <span class="n">PyDict_MergeFromSeq2</span><span class="p">(</span><span class="n">a</span><span class="p">,</span> <span class="n">seq2</span><span class="p">,</span> <span class="n">override</span><span class="p">)</span><span class="o">:</span> <span class="k">for</span> <span class="n">key</span><span class="p">,</span> <span class="n">value</span> <span class="n">in</span> <span class="n">seq2</span><span class="o">:</span> <span class="k">if</span> <span class="n">override</span> <span class="n">or</span> <span class="n">key</span> <span class="n">not</span> <span class="n">in</span> <span class="n">a</span><span class="o">:</span> <span class="n">a</span><span class="p">[</span><span class="n">key</span><span class="p">]</span> <span class="o">=</span> <span class="n">value</span> </pre></div> </div> <p class="versionadded"> <span class="versionmodified">New in version 2.2.</span></p> </dd></dl> </div> </div> </div> </div> <div class="sphinxsidebar"> <div class="sphinxsidebarwrapper"> <h4>Previous topic</h4> <p class="topless"><a href="list.html" title="previous chapter">List Objects</a></p> <h4>Next topic</h4> <p class="topless"><a href="class.html" title="next chapter">Class and Instance Objects</a></p> <h3>This Page</h3> <ul class="this-page-menu"> <li><a href="../bugs.html">Report a Bug</a></li> <li><a href="../_sources/c-api/dict.txt" rel="nofollow">Show Source</a></li> </ul> <div id="searchbox" style="display: none"> <h3>Quick search</h3> <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> <p class="searchtip" style="font-size: 90%"> Enter search terms or a module, class or function name. </p> </div> <script type="text/javascript">$('#searchbox').show(0);</script> </div> </div> <div class="clearer"></div> </div> <div class="related"> <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="class.html" title="Class and Instance Objects" >next</a> |</li> <li class="right" > <a href="list.html" title="List Objects" >previous</a> |</li> <li><img src="../_static/py.png" alt="" style="vertical-align: middle; margin-top: -1px"/></li> <li><a href="http://www.python.org/">Python</a> »</li> <li> <a href="../index.html">Python 2.7.5 documentation</a> » </li> <li><a href="index.html" >Python/C API Reference Manual</a> »</li> <li><a href="concrete.html" >Concrete Objects Layer</a> »</li> </ul> </div> <div class="footer"> © <a href="../copyright.html">Copyright</a> 1990-2020, Python Software Foundation. <br /> The Python Software Foundation is a non-profit corporation. <a href="http://www.python.org/psf/donations/">Please donate.</a> <br /> Last updated on Oct 13, 2020. <a href="../bugs.html">Found a bug</a>? <br /> Created using <a href="http://sphinx.pocoo.org/">Sphinx</a> 1.1.3. </div> </body> </html>