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<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="c.PyDictObject">
<code class="sig-name descname">PyDictObject</code><a class="headerlink" href="#c.PyDictObject" title="Permalink to this definition">¶</a></dt>
<dd><p>This subtype 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> represents a Python dictionary object.</p>
</dd></dl>
<dl class="var">
<dt id="c.PyDict_Type">
<a class="reference internal" href="type.html#c.PyTypeObject" title="PyTypeObject">PyTypeObject</a> <code class="sig-name descname">PyDict_Type</code><a class="headerlink" href="#c.PyDict_Type" title="Permalink to this definition">¶</a></dt>
<dd><p>This instance of <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> represents the Python dictionary
type. This is the same object as <a class="reference internal" href="../library/stdtypes.html#dict" title="dict"><code class="xref py py-class docutils literal notranslate"><span class="pre">dict</span></code></a> in the Python layer.</p>
</dd></dl>
<dl class="function">
<dt id="c.PyDict_Check">
int <code class="sig-name descname">PyDict_Check</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *p</em><span class="sig-paren">)</span><a class="headerlink" href="#c.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>
</dd></dl>
<dl class="function">
<dt id="c.PyDict_CheckExact">
int <code class="sig-name descname">PyDict_CheckExact</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *p</em><span class="sig-paren">)</span><a class="headerlink" href="#c.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>
</dd></dl>
<dl class="function">
<dt id="c.PyDict_New">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="sig-name descname">PyDict_New</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#c.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 <code class="docutils literal notranslate"><span class="pre">NULL</span></code> on failure.</p>
</dd></dl>
<dl class="function">
<dt id="c.PyDictProxy_New">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="sig-name descname">PyDictProxy_New</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *mapping</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyDictProxy_New" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Return a <a class="reference internal" href="../library/types.html#types.MappingProxyType" title="types.MappingProxyType"><code class="xref py py-class docutils literal notranslate"><span class="pre">types.MappingProxyType</span></code></a> object for a mapping which
enforces read-only behavior. This is normally used to create a view to
prevent modification of the dictionary for non-dynamic class types.</p>
</dd></dl>
<dl class="function">
<dt id="c.PyDict_Clear">
void <code class="sig-name descname">PyDict_Clear</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *p</em><span class="sig-paren">)</span><a class="headerlink" href="#c.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="c.PyDict_Contains">
int <code class="sig-name descname">PyDict_Contains</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *p</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.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 <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">key</span> <span class="pre">in</span> <span class="pre">p</span></code>.</p>
</dd></dl>
<dl class="function">
<dt id="c.PyDict_Copy">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="sig-name descname">PyDict_Copy</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *p</em><span class="sig-paren">)</span><a class="headerlink" href="#c.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>
</dd></dl>
<dl class="function">
<dt id="c.PyDict_SetItem">
int <code class="sig-name descname">PyDict_SetItem</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *p</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> *val</em><span class="sig-paren">)</span><a class="headerlink" href="#c.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"><span class="xref std std-term">hashable</span></a>; if it isn’t, <a class="reference internal" href="../library/exceptions.html#TypeError" title="TypeError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">TypeError</span></code></a> will be raised. Return
<code class="docutils literal notranslate"><span class="pre">0</span></code> on success or <code class="docutils literal notranslate"><span class="pre">-1</span></code> on failure.</p>
</dd></dl>
<dl class="function">
<dt id="c.PyDict_SetItemString">
int <code class="sig-name descname">PyDict_SetItemString</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *p</em>, const char<em> *key</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *val</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyDict_SetItemString" title="Permalink to this definition">¶</a></dt>
<dd><p id="index-1">Insert <em>value</em> into the dictionary <em>p</em> using <em>key</em> as a key. <em>key</em> should
be a <code class="xref c c-type docutils literal notranslate"><span class="pre">const</span> <span class="pre">char*</span></code>. The key object is created using
<code class="docutils literal notranslate"><span class="pre">PyUnicode_FromString(key)</span></code>. Return <code class="docutils literal notranslate"><span class="pre">0</span></code> on success or <code class="docutils literal notranslate"><span class="pre">-1</span></code> on
failure.</p>
</dd></dl>
<dl class="function">
<dt id="c.PyDict_DelItem">
int <code class="sig-name descname">PyDict_DelItem</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *p</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.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#TypeError" title="TypeError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">TypeError</span></code></a> is raised. Return <code class="docutils literal notranslate"><span class="pre">0</span></code> on success or <code class="docutils literal notranslate"><span class="pre">-1</span></code>
on failure.</p>
</dd></dl>
<dl class="function">
<dt id="c.PyDict_DelItemString">
int <code class="sig-name descname">PyDict_DelItemString</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *p</em>, const char<em> *key</em><span class="sig-paren">)</span><a class="headerlink" href="#c.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 <code class="docutils literal notranslate"><span class="pre">0</span></code> on success or <code class="docutils literal notranslate"><span class="pre">-1</span></code> on failure.</p>
</dd></dl>
<dl class="function">
<dt id="c.PyDict_GetItem">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="sig-name descname">PyDict_GetItem</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *p</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.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 <code class="docutils literal notranslate"><span class="pre">NULL</span></code>
if the key <em>key</em> is not present, but <em>without</em> setting an exception.</p>
<p>Note that exceptions which occur while calling <a class="reference internal" href="../reference/datamodel.html#object.__hash__" title="object.__hash__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">__hash__()</span></code></a> and
<a class="reference internal" href="../reference/datamodel.html#object.__eq__" title="object.__eq__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">__eq__()</span></code></a> methods will get suppressed.
To get error reporting use <a class="reference internal" href="#c.PyDict_GetItemWithError" title="PyDict_GetItemWithError"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyDict_GetItemWithError()</span></code></a> instead.</p>
</dd></dl>
<dl class="function">
<dt id="c.PyDict_GetItemWithError">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="sig-name descname">PyDict_GetItemWithError</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *p</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.PyDict_GetItemWithError" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: Borrowed reference.</em><p>Variant of <a class="reference internal" href="#c.PyDict_GetItem" title="PyDict_GetItem"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyDict_GetItem()</span></code></a> that does not suppress
exceptions. Return <code class="docutils literal notranslate"><span class="pre">NULL</span></code> <strong>with</strong> an exception set if an exception
occurred. Return <code class="docutils literal notranslate"><span class="pre">NULL</span></code> <strong>without</strong> an exception set if the key
wasn’t present.</p>
</dd></dl>
<dl class="function">
<dt id="c.PyDict_GetItemString">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="sig-name descname">PyDict_GetItemString</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *p</em>, const char<em> *key</em><span class="sig-paren">)</span><a class="headerlink" href="#c.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="#c.PyDict_GetItem" title="PyDict_GetItem"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyDict_GetItem()</span></code></a>, but <em>key</em> is specified as a
<code class="xref c c-type docutils literal notranslate"><span class="pre">const</span> <span class="pre">char*</span></code>, rather than a <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>.</p>
<p>Note that exceptions which occur while calling <a class="reference internal" href="../reference/datamodel.html#object.__hash__" title="object.__hash__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">__hash__()</span></code></a> and
<a class="reference internal" href="../reference/datamodel.html#object.__eq__" title="object.__eq__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">__eq__()</span></code></a> methods and creating a temporary string object
will get suppressed.
To get error reporting use <a class="reference internal" href="#c.PyDict_GetItemWithError" title="PyDict_GetItemWithError"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyDict_GetItemWithError()</span></code></a> instead.</p>
</dd></dl>
<dl class="function">
<dt id="c.PyDict_SetDefault">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="sig-name descname">PyDict_SetDefault</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *p</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> *defaultobj</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyDict_SetDefault" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: Borrowed reference.</em><p>This is the same as the Python-level <a class="reference internal" href="../library/stdtypes.html#dict.setdefault" title="dict.setdefault"><code class="xref py py-meth docutils literal notranslate"><span class="pre">dict.setdefault()</span></code></a>. If present, it
returns the value corresponding to <em>key</em> from the dictionary <em>p</em>. If the key
is not in the dict, it is inserted with value <em>defaultobj</em> and <em>defaultobj</em>
is returned. This function evaluates the hash function of <em>key</em> only once,
instead of evaluating it independently for the lookup and the insertion.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 3.4.</span></p>
</div>
</dd></dl>
<dl class="function">
<dt id="c.PyDict_Items">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="sig-name descname">PyDict_Items</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *p</em><span class="sig-paren">)</span><a class="headerlink" href="#c.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#c.PyListObject" title="PyListObject"><code class="xref c c-type docutils literal notranslate"><span class="pre">PyListObject</span></code></a> containing all the items from the dictionary.</p>
</dd></dl>
<dl class="function">
<dt id="c.PyDict_Keys">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="sig-name descname">PyDict_Keys</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *p</em><span class="sig-paren">)</span><a class="headerlink" href="#c.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#c.PyListObject" title="PyListObject"><code class="xref c c-type docutils literal notranslate"><span class="pre">PyListObject</span></code></a> containing all the keys from the dictionary.</p>
</dd></dl>
<dl class="function">
<dt id="c.PyDict_Values">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="sig-name descname">PyDict_Values</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *p</em><span class="sig-paren">)</span><a class="headerlink" href="#c.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#c.PyListObject" title="PyListObject"><code class="xref c c-type docutils literal notranslate"><span class="pre">PyListObject</span></code></a> containing all the values from the dictionary
<em>p</em>.</p>
</dd></dl>
<dl class="function">
<dt id="c.PyDict_Size">
Py_ssize_t <code class="sig-name descname">PyDict_Size</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *p</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyDict_Size" title="Permalink to this definition">¶</a></dt>
<dd><p id="index-2">Return the number of items in the dictionary. This is equivalent to
<code class="docutils literal notranslate"><span class="pre">len(p)</span></code> on a dictionary.</p>
</dd></dl>
<dl class="function">
<dt id="c.PyDict_Next">
int <code class="sig-name descname">PyDict_Next</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *p</em>, Py_ssize_t<em> *ppos</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> **pkey</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> **pvalue</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyDict_Next" title="Permalink to this definition">¶</a></dt>
<dd><p>Iterate over all key-value pairs in the dictionary <em>p</em>. The
<code class="xref c c-type docutils literal notranslate"><span class="pre">Py_ssize_t</span></code> referred to by <em>ppos</em> must be initialized to <code class="docutils literal notranslate"><span class="pre">0</span></code>
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#c.PyObject" title="PyObject"><code class="xref c c-type docutils literal notranslate"><span class="pre">PyObject*</span></code></a> variables that will be filled in with each key
and value, respectively, or may be <code class="docutils literal notranslate"><span class="pre">NULL</span></code>. 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 notranslate"><div class="highlight"><pre><span></span><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 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 notranslate"><div class="highlight"><pre><span></span><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">long</span> <span class="n">i</span> <span class="o">=</span> <span class="n">PyLong_AsLong</span><span class="p">(</span><span class="n">value</span><span class="p">);</span>
<span class="k">if</span> <span class="p">(</span><span class="n">i</span> <span class="o">==</span> <span class="o">-</span><span class="mi">1</span> <span class="o">&&</span> <span class="n">PyErr_Occurred</span><span class="p">())</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">PyObject</span> <span class="o">*</span><span class="n">o</span> <span class="o">=</span> <span class="n">PyLong_FromLong</span><span class="p">(</span><span class="n">i</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">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>
</dd></dl>
<dl class="function">
<dt id="c.PyDict_Merge">
int <code class="sig-name descname">PyDict_Merge</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *a</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *b</em>, int<em> override</em><span class="sig-paren">)</span><a class="headerlink" href="#c.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#c.PyMapping_Keys" title="PyMapping_Keys"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyMapping_Keys()</span></code></a>
and <a class="reference internal" href="object.html#c.PyObject_GetItem" title="PyObject_GetItem"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyObject_GetItem()</span></code></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 <code class="docutils literal notranslate"><span class="pre">0</span></code> on
success or <code class="docutils literal notranslate"><span class="pre">-1</span></code> if an exception was raised.</p>
</dd></dl>
<dl class="function">
<dt id="c.PyDict_Update">
int <code class="sig-name descname">PyDict_Update</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *a</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *b</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyDict_Update" title="Permalink to this definition">¶</a></dt>
<dd><p>This is the same as <code class="docutils literal notranslate"><span class="pre">PyDict_Merge(a,</span> <span class="pre">b,</span> <span class="pre">1)</span></code> in C, and is similar to
<code class="docutils literal notranslate"><span class="pre">a.update(b)</span></code> in Python except that <a class="reference internal" href="#c.PyDict_Update" title="PyDict_Update"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyDict_Update()</span></code></a> doesn’t fall
back to the iterating over a sequence of key value pairs if the second
argument has no “keys” attribute. Return <code class="docutils literal notranslate"><span class="pre">0</span></code> on success or <code class="docutils literal notranslate"><span class="pre">-1</span></code> if an
exception was raised.</p>
</dd></dl>
<dl class="function">
<dt id="c.PyDict_MergeFromSeq2">
int <code class="sig-name descname">PyDict_MergeFromSeq2</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *a</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *seq2</em>, int<em> override</em><span class="sig-paren">)</span><a class="headerlink" href="#c.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 <code class="docutils literal notranslate"><span class="pre">0</span></code> on success or <code class="docutils literal notranslate"><span class="pre">-1</span></code>
if an exception was raised. Equivalent Python (except for the return
value):</p>
<div class="highlight-c notranslate"><div class="highlight"><pre><span></span><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="nl">seq2</span><span class="p">:</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="nl">a</span><span class="p">:</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>
</dd></dl>
<dl class="function">
<dt id="c.PyDict_ClearFreeList">
int <code class="sig-name descname">PyDict_ClearFreeList</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyDict_ClearFreeList" title="Permalink to this definition">¶</a></dt>
<dd><p>Clear the free list. Return the total number of freed items.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 3.3.</span></p>
</div>
</dd></dl>
</div>
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