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<div class="section" id="module-html.parser">
<span id="html-parser-simple-html-and-xhtml-parser"></span><h1>20.2. <a class="reference internal" href="#module-html.parser" title="html.parser: A simple parser that can handle HTML and XHTML."><tt class="xref py py-mod docutils literal"><span class="pre">html.parser</span></tt></a> — Simple HTML and XHTML parser<a class="headerlink" href="#module-html.parser" title="Permalink to this headline">¶</a></h1>
<p id="index-0"><strong>Source code:</strong> <a class="reference external" href="https://hg.python.org/cpython/file/3.4/Lib/html/parser.py">Lib/html/parser.py</a></p>
<hr class="docutils" />
<p>This module defines a class <a class="reference internal" href="#html.parser.HTMLParser" title="html.parser.HTMLParser"><tt class="xref py py-class docutils literal"><span class="pre">HTMLParser</span></tt></a> which serves as the basis for
parsing text files formatted in HTML (HyperText Mark-up Language) and XHTML.</p>
<dl class="class">
<dt id="html.parser.HTMLParser">
<em class="property">class </em><tt class="descclassname">html.parser.</tt><tt class="descname">HTMLParser</tt><big>(</big><em>strict=False</em>, <em>*</em>, <em>convert_charrefs=False</em><big>)</big><a class="headerlink" href="#html.parser.HTMLParser" title="Permalink to this definition">¶</a></dt>
<dd><p>Create a parser instance.</p>
<p>If <em>convert_charrefs</em> is <tt class="docutils literal"><span class="pre">True</span></tt> (default: <tt class="docutils literal"><span class="pre">False</span></tt>), all character
references (except the ones in <tt class="docutils literal"><span class="pre">script</span></tt>/<tt class="docutils literal"><span class="pre">style</span></tt> elements) are
automatically converted to the corresponding Unicode characters.
The use of <tt class="docutils literal"><span class="pre">convert_charrefs=True</span></tt> is encouraged and will become
the default in Python 3.5.</p>
<p>If <em>strict</em> is <tt class="docutils literal"><span class="pre">False</span></tt> (the default), the parser will accept and parse
invalid markup. If <em>strict</em> is <tt class="docutils literal"><span class="pre">True</span></tt> the parser will raise an
<a class="reference internal" href="#html.parser.HTMLParseError" title="html.parser.HTMLParseError"><tt class="xref py py-exc docutils literal"><span class="pre">HTMLParseError</span></tt></a> exception instead <a class="footnote-reference" href="#id2" id="id1">[1]</a> when it’s not
able to parse the markup. The use of <tt class="docutils literal"><span class="pre">strict=True</span></tt> is discouraged and
the <em>strict</em> argument is deprecated.</p>
<p>An <a class="reference internal" href="#html.parser.HTMLParser" title="html.parser.HTMLParser"><tt class="xref py py-class docutils literal"><span class="pre">HTMLParser</span></tt></a> instance is fed HTML data and calls handler methods
when start tags, end tags, text, comments, and other markup elements are
encountered. The user should subclass <a class="reference internal" href="#html.parser.HTMLParser" title="html.parser.HTMLParser"><tt class="xref py py-class docutils literal"><span class="pre">HTMLParser</span></tt></a> and override its
methods to implement the desired behavior.</p>
<p>This parser does not check that end tags match start tags or call the end-tag
handler for elements which are closed implicitly by closing an outer element.</p>
<div class="versionchanged">
<p><span class="versionmodified">Changed in version 3.2: </span><em>strict</em> argument added.</p>
</div>
<div class="deprecated-removed">
<p><span class="versionmodified">Deprecated since version 3.3, will be removed in version 3.5: </span>The <em>strict</em> argument and the strict mode have been deprecated.
The parser is now able to accept and parse invalid markup too.</p>
</div>
<div class="versionchanged">
<p><span class="versionmodified">Changed in version 3.4: </span><em>convert_charrefs</em> keyword argument added.</p>
</div>
</dd></dl>
<p>An exception is defined as well:</p>
<dl class="exception">
<dt id="html.parser.HTMLParseError">
<em class="property">exception </em><tt class="descclassname">html.parser.</tt><tt class="descname">HTMLParseError</tt><a class="headerlink" href="#html.parser.HTMLParseError" title="Permalink to this definition">¶</a></dt>
<dd><p>Exception raised by the <a class="reference internal" href="#html.parser.HTMLParser" title="html.parser.HTMLParser"><tt class="xref py py-class docutils literal"><span class="pre">HTMLParser</span></tt></a> class when it encounters an error
while parsing and <em>strict</em> is <tt class="docutils literal"><span class="pre">True</span></tt>. This exception provides three
attributes: <tt class="xref py py-attr docutils literal"><span class="pre">msg</span></tt> is a brief message explaining the error,
<tt class="xref py py-attr docutils literal"><span class="pre">lineno</span></tt> is the number of the line on which the broken construct was
detected, and <tt class="xref py py-attr docutils literal"><span class="pre">offset</span></tt> is the number of characters into the line at
which the construct starts.</p>
<div class="deprecated-removed">
<p><span class="versionmodified">Deprecated since version 3.3, will be removed in version 3.5: </span>This exception has been deprecated because it’s never raised by the parser
(when the default non-strict mode is used).</p>
</div>
</dd></dl>
<div class="section" id="example-html-parser-application">
<h2>20.2.1. Example HTML Parser Application<a class="headerlink" href="#example-html-parser-application" title="Permalink to this headline">¶</a></h2>
<p>As a basic example, below is a simple HTML parser that uses the
<a class="reference internal" href="#html.parser.HTMLParser" title="html.parser.HTMLParser"><tt class="xref py py-class docutils literal"><span class="pre">HTMLParser</span></tt></a> class to print out start tags, end tags, and data
as they are encountered:</p>
<div class="highlight-python3"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">html.parser</span> <span class="k">import</span> <span class="n">HTMLParser</span>
<span class="k">class</span> <span class="nc">MyHTMLParser</span><span class="p">(</span><span class="n">HTMLParser</span><span class="p">):</span>
<span class="k">def</span> <span class="nf">handle_starttag</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">tag</span><span class="p">,</span> <span class="n">attrs</span><span class="p">):</span>
<span class="nb">print</span><span class="p">(</span><span class="s">"Encountered a start tag:"</span><span class="p">,</span> <span class="n">tag</span><span class="p">)</span>
<span class="k">def</span> <span class="nf">handle_endtag</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">tag</span><span class="p">):</span>
<span class="nb">print</span><span class="p">(</span><span class="s">"Encountered an end tag :"</span><span class="p">,</span> <span class="n">tag</span><span class="p">)</span>
<span class="k">def</span> <span class="nf">handle_data</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">data</span><span class="p">):</span>
<span class="nb">print</span><span class="p">(</span><span class="s">"Encountered some data :"</span><span class="p">,</span> <span class="n">data</span><span class="p">)</span>
<span class="n">parser</span> <span class="o">=</span> <span class="n">MyHTMLParser</span><span class="p">()</span>
<span class="n">parser</span><span class="o">.</span><span class="n">feed</span><span class="p">(</span><span class="s">'<html><head><title>Test</title></head>'</span>
<span class="s">'<body><h1>Parse me!</h1></body></html>'</span><span class="p">)</span>
</pre></div>
</div>
<p>The output will then be:</p>
<div class="highlight-python3"><div class="highlight"><pre>Encountered a start tag: html
Encountered a start tag: head
Encountered a start tag: title
Encountered some data : Test
Encountered an end tag : title
Encountered an end tag : head
Encountered a start tag: body
Encountered a start tag: h1
Encountered some data : Parse me!
Encountered an end tag : h1
Encountered an end tag : body
Encountered an end tag : html
</pre></div>
</div>
</div>
<div class="section" id="htmlparser-methods">
<h2>20.2.2. <a class="reference internal" href="#html.parser.HTMLParser" title="html.parser.HTMLParser"><tt class="xref py py-class docutils literal"><span class="pre">HTMLParser</span></tt></a> Methods<a class="headerlink" href="#htmlparser-methods" title="Permalink to this headline">¶</a></h2>
<p><a class="reference internal" href="#html.parser.HTMLParser" title="html.parser.HTMLParser"><tt class="xref py py-class docutils literal"><span class="pre">HTMLParser</span></tt></a> instances have the following methods:</p>
<dl class="method">
<dt id="html.parser.HTMLParser.feed">
<tt class="descclassname">HTMLParser.</tt><tt class="descname">feed</tt><big>(</big><em>data</em><big>)</big><a class="headerlink" href="#html.parser.HTMLParser.feed" title="Permalink to this definition">¶</a></dt>
<dd><p>Feed some text to the parser. It is processed insofar as it consists of
complete elements; incomplete data is buffered until more data is fed or
<a class="reference internal" href="#html.parser.HTMLParser.close" title="html.parser.HTMLParser.close"><tt class="xref py py-meth docutils literal"><span class="pre">close()</span></tt></a> is called. <em>data</em> must be <a class="reference internal" href="stdtypes.html#str" title="str"><tt class="xref py py-class docutils literal"><span class="pre">str</span></tt></a>.</p>
</dd></dl>
<dl class="method">
<dt id="html.parser.HTMLParser.close">
<tt class="descclassname">HTMLParser.</tt><tt class="descname">close</tt><big>(</big><big>)</big><a class="headerlink" href="#html.parser.HTMLParser.close" title="Permalink to this definition">¶</a></dt>
<dd><p>Force processing of all buffered data as if it were followed by an end-of-file
mark. This method may be redefined by a derived class to define additional
processing at the end of the input, but the redefined version should always call
the <a class="reference internal" href="#html.parser.HTMLParser" title="html.parser.HTMLParser"><tt class="xref py py-class docutils literal"><span class="pre">HTMLParser</span></tt></a> base class method <a class="reference internal" href="#html.parser.HTMLParser.close" title="html.parser.HTMLParser.close"><tt class="xref py py-meth docutils literal"><span class="pre">close()</span></tt></a>.</p>
</dd></dl>
<dl class="method">
<dt id="html.parser.HTMLParser.reset">
<tt class="descclassname">HTMLParser.</tt><tt class="descname">reset</tt><big>(</big><big>)</big><a class="headerlink" href="#html.parser.HTMLParser.reset" title="Permalink to this definition">¶</a></dt>
<dd><p>Reset the instance. Loses all unprocessed data. This is called implicitly at
instantiation time.</p>
</dd></dl>
<dl class="method">
<dt id="html.parser.HTMLParser.getpos">
<tt class="descclassname">HTMLParser.</tt><tt class="descname">getpos</tt><big>(</big><big>)</big><a class="headerlink" href="#html.parser.HTMLParser.getpos" title="Permalink to this definition">¶</a></dt>
<dd><p>Return current line number and offset.</p>
</dd></dl>
<dl class="method">
<dt id="html.parser.HTMLParser.get_starttag_text">
<tt class="descclassname">HTMLParser.</tt><tt class="descname">get_starttag_text</tt><big>(</big><big>)</big><a class="headerlink" href="#html.parser.HTMLParser.get_starttag_text" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the text of the most recently opened start tag. This should not normally
be needed for structured processing, but may be useful in dealing with HTML “as
deployed” or for re-generating input with minimal changes (whitespace between
attributes can be preserved, etc.).</p>
</dd></dl>
<p>The following methods are called when data or markup elements are encountered
and they are meant to be overridden in a subclass. The base class
implementations do nothing (except for <a class="reference internal" href="#html.parser.HTMLParser.handle_startendtag" title="html.parser.HTMLParser.handle_startendtag"><tt class="xref py py-meth docutils literal"><span class="pre">handle_startendtag()</span></tt></a>):</p>
<dl class="method">
<dt id="html.parser.HTMLParser.handle_starttag">
<tt class="descclassname">HTMLParser.</tt><tt class="descname">handle_starttag</tt><big>(</big><em>tag</em>, <em>attrs</em><big>)</big><a class="headerlink" href="#html.parser.HTMLParser.handle_starttag" title="Permalink to this definition">¶</a></dt>
<dd><p>This method is called to handle the start of a tag (e.g. <tt class="docutils literal"><span class="pre"><div</span> <span class="pre">id="main"></span></tt>).</p>
<p>The <em>tag</em> argument is the name of the tag converted to lower case. The <em>attrs</em>
argument is a list of <tt class="docutils literal"><span class="pre">(name,</span> <span class="pre">value)</span></tt> pairs containing the attributes found
inside the tag’s <tt class="docutils literal"><span class="pre"><></span></tt> brackets. The <em>name</em> will be translated to lower case,
and quotes in the <em>value</em> have been removed, and character and entity references
have been replaced.</p>
<p>For instance, for the tag <tt class="docutils literal"><span class="pre"><A</span> <span class="pre">HREF="http://www.cwi.nl/"></span></tt>, this method
would be called as <tt class="docutils literal"><span class="pre">handle_starttag('a',</span> <span class="pre">[('href',</span> <span class="pre">'http://www.cwi.nl/')])</span></tt>.</p>
<p>All entity references from <a class="reference internal" href="html.entities.html#module-html.entities" title="html.entities: Definitions of HTML general entities."><tt class="xref py py-mod docutils literal"><span class="pre">html.entities</span></tt></a> are replaced in the attribute
values.</p>
</dd></dl>
<dl class="method">
<dt id="html.parser.HTMLParser.handle_endtag">
<tt class="descclassname">HTMLParser.</tt><tt class="descname">handle_endtag</tt><big>(</big><em>tag</em><big>)</big><a class="headerlink" href="#html.parser.HTMLParser.handle_endtag" title="Permalink to this definition">¶</a></dt>
<dd><p>This method is called to handle the end tag of an element (e.g. <tt class="docutils literal"><span class="pre"></div></span></tt>).</p>
<p>The <em>tag</em> argument is the name of the tag converted to lower case.</p>
</dd></dl>
<dl class="method">
<dt id="html.parser.HTMLParser.handle_startendtag">
<tt class="descclassname">HTMLParser.</tt><tt class="descname">handle_startendtag</tt><big>(</big><em>tag</em>, <em>attrs</em><big>)</big><a class="headerlink" href="#html.parser.HTMLParser.handle_startendtag" title="Permalink to this definition">¶</a></dt>
<dd><p>Similar to <a class="reference internal" href="#html.parser.HTMLParser.handle_starttag" title="html.parser.HTMLParser.handle_starttag"><tt class="xref py py-meth docutils literal"><span class="pre">handle_starttag()</span></tt></a>, but called when the parser encounters an
XHTML-style empty tag (<tt class="docutils literal"><span class="pre"><img</span> <span class="pre">...</span> <span class="pre">/></span></tt>). This method may be overridden by
subclasses which require this particular lexical information; the default
implementation simply calls <a class="reference internal" href="#html.parser.HTMLParser.handle_starttag" title="html.parser.HTMLParser.handle_starttag"><tt class="xref py py-meth docutils literal"><span class="pre">handle_starttag()</span></tt></a> and <a class="reference internal" href="#html.parser.HTMLParser.handle_endtag" title="html.parser.HTMLParser.handle_endtag"><tt class="xref py py-meth docutils literal"><span class="pre">handle_endtag()</span></tt></a>.</p>
</dd></dl>
<dl class="method">
<dt id="html.parser.HTMLParser.handle_data">
<tt class="descclassname">HTMLParser.</tt><tt class="descname">handle_data</tt><big>(</big><em>data</em><big>)</big><a class="headerlink" href="#html.parser.HTMLParser.handle_data" title="Permalink to this definition">¶</a></dt>
<dd><p>This method is called to process arbitrary data (e.g. text nodes and the
content of <tt class="docutils literal"><span class="pre"><script>...</script></span></tt> and <tt class="docutils literal"><span class="pre"><style>...</style></span></tt>).</p>
</dd></dl>
<dl class="method">
<dt id="html.parser.HTMLParser.handle_entityref">
<tt class="descclassname">HTMLParser.</tt><tt class="descname">handle_entityref</tt><big>(</big><em>name</em><big>)</big><a class="headerlink" href="#html.parser.HTMLParser.handle_entityref" title="Permalink to this definition">¶</a></dt>
<dd><p>This method is called to process a named character reference of the form
<tt class="docutils literal"><span class="pre">&name;</span></tt> (e.g. <tt class="docutils literal"><span class="pre">&gt;</span></tt>), where <em>name</em> is a general entity reference
(e.g. <tt class="docutils literal"><span class="pre">'gt'</span></tt>). This method is never called if <em>convert_charrefs</em> is
<tt class="docutils literal"><span class="pre">True</span></tt>.</p>
</dd></dl>
<dl class="method">
<dt id="html.parser.HTMLParser.handle_charref">
<tt class="descclassname">HTMLParser.</tt><tt class="descname">handle_charref</tt><big>(</big><em>name</em><big>)</big><a class="headerlink" href="#html.parser.HTMLParser.handle_charref" title="Permalink to this definition">¶</a></dt>
<dd><p>This method is called to process decimal and hexadecimal numeric character
references of the form <tt class="docutils literal"><span class="pre">&#NNN;</span></tt> and <tt class="docutils literal"><span class="pre">&#xNNN;</span></tt>. For example, the decimal
equivalent for <tt class="docutils literal"><span class="pre">&gt;</span></tt> is <tt class="docutils literal"><span class="pre">&#62;</span></tt>, whereas the hexadecimal is <tt class="docutils literal"><span class="pre">&#x3E;</span></tt>;
in this case the method will receive <tt class="docutils literal"><span class="pre">'62'</span></tt> or <tt class="docutils literal"><span class="pre">'x3E'</span></tt>. This method
is never called if <em>convert_charrefs</em> is <tt class="docutils literal"><span class="pre">True</span></tt>.</p>
</dd></dl>
<dl class="method">
<dt id="html.parser.HTMLParser.handle_comment">
<tt class="descclassname">HTMLParser.</tt><tt class="descname">handle_comment</tt><big>(</big><em>data</em><big>)</big><a class="headerlink" href="#html.parser.HTMLParser.handle_comment" title="Permalink to this definition">¶</a></dt>
<dd><p>This method is called when a comment is encountered (e.g. <tt class="docutils literal"><span class="pre"><!--comment--></span></tt>).</p>
<p>For example, the comment <tt class="docutils literal"><span class="pre"><!--</span> <span class="pre">comment</span> <span class="pre">--></span></tt> will cause this method to be
called with the argument <tt class="docutils literal"><span class="pre">'</span> <span class="pre">comment</span> <span class="pre">'</span></tt>.</p>
<p>The content of Internet Explorer conditional comments (condcoms) will also be
sent to this method, so, for <tt class="docutils literal"><span class="pre"><!--[if</span> <span class="pre">IE</span> <span class="pre">9]>IE9-specific</span> <span class="pre">content<![endif]--></span></tt>,
this method will receive <tt class="docutils literal"><span class="pre">'[if</span> <span class="pre">IE</span> <span class="pre">9]>IE-specific</span> <span class="pre">content<![endif]'</span></tt>.</p>
</dd></dl>
<dl class="method">
<dt id="html.parser.HTMLParser.handle_decl">
<tt class="descclassname">HTMLParser.</tt><tt class="descname">handle_decl</tt><big>(</big><em>decl</em><big>)</big><a class="headerlink" href="#html.parser.HTMLParser.handle_decl" title="Permalink to this definition">¶</a></dt>
<dd><p>This method is called to handle an HTML doctype declaration (e.g.
<tt class="docutils literal"><span class="pre"><!DOCTYPE</span> <span class="pre">html></span></tt>).</p>
<p>The <em>decl</em> parameter will be the entire contents of the declaration inside
the <tt class="docutils literal"><span class="pre"><!...></span></tt> markup (e.g. <tt class="docutils literal"><span class="pre">'DOCTYPE</span> <span class="pre">html'</span></tt>).</p>
</dd></dl>
<dl class="method">
<dt id="html.parser.HTMLParser.handle_pi">
<tt class="descclassname">HTMLParser.</tt><tt class="descname">handle_pi</tt><big>(</big><em>data</em><big>)</big><a class="headerlink" href="#html.parser.HTMLParser.handle_pi" title="Permalink to this definition">¶</a></dt>
<dd><p>Method called when a processing instruction is encountered. The <em>data</em>
parameter will contain the entire processing instruction. For example, for the
processing instruction <tt class="docutils literal"><span class="pre"><?proc</span> <span class="pre">color='red'></span></tt>, this method would be called as
<tt class="docutils literal"><span class="pre">handle_pi("proc</span> <span class="pre">color='red'")</span></tt>. It is intended to be overridden by a derived
class; the base class implementation does nothing.</p>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">The <a class="reference internal" href="#html.parser.HTMLParser" title="html.parser.HTMLParser"><tt class="xref py py-class docutils literal"><span class="pre">HTMLParser</span></tt></a> class uses the SGML syntactic rules for processing
instructions. An XHTML processing instruction using the trailing <tt class="docutils literal"><span class="pre">'?'</span></tt> will
cause the <tt class="docutils literal"><span class="pre">'?'</span></tt> to be included in <em>data</em>.</p>
</div>
</dd></dl>
<dl class="method">
<dt id="html.parser.HTMLParser.unknown_decl">
<tt class="descclassname">HTMLParser.</tt><tt class="descname">unknown_decl</tt><big>(</big><em>data</em><big>)</big><a class="headerlink" href="#html.parser.HTMLParser.unknown_decl" title="Permalink to this definition">¶</a></dt>
<dd><p>This method is called when an unrecognized declaration is read by the parser.</p>
<p>The <em>data</em> parameter will be the entire contents of the declaration inside
the <tt class="docutils literal"><span class="pre"><![...]></span></tt> markup. It is sometimes useful to be overridden by a
derived class. The base class implementation raises an <a class="reference internal" href="#html.parser.HTMLParseError" title="html.parser.HTMLParseError"><tt class="xref py py-exc docutils literal"><span class="pre">HTMLParseError</span></tt></a>
when <em>strict</em> is <tt class="docutils literal"><span class="pre">True</span></tt>.</p>
</dd></dl>
</div>
<div class="section" id="examples">
<span id="htmlparser-examples"></span><h2>20.2.3. Examples<a class="headerlink" href="#examples" title="Permalink to this headline">¶</a></h2>
<p>The following class implements a parser that will be used to illustrate more
examples:</p>
<div class="highlight-python3"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">html.parser</span> <span class="k">import</span> <span class="n">HTMLParser</span>
<span class="kn">from</span> <span class="nn">html.entities</span> <span class="k">import</span> <span class="n">name2codepoint</span>
<span class="k">class</span> <span class="nc">MyHTMLParser</span><span class="p">(</span><span class="n">HTMLParser</span><span class="p">):</span>
<span class="k">def</span> <span class="nf">handle_starttag</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">tag</span><span class="p">,</span> <span class="n">attrs</span><span class="p">):</span>
<span class="nb">print</span><span class="p">(</span><span class="s">"Start tag:"</span><span class="p">,</span> <span class="n">tag</span><span class="p">)</span>
<span class="k">for</span> <span class="n">attr</span> <span class="ow">in</span> <span class="n">attrs</span><span class="p">:</span>
<span class="nb">print</span><span class="p">(</span><span class="s">" attr:"</span><span class="p">,</span> <span class="n">attr</span><span class="p">)</span>
<span class="k">def</span> <span class="nf">handle_endtag</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">tag</span><span class="p">):</span>
<span class="nb">print</span><span class="p">(</span><span class="s">"End tag :"</span><span class="p">,</span> <span class="n">tag</span><span class="p">)</span>
<span class="k">def</span> <span class="nf">handle_data</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">data</span><span class="p">):</span>
<span class="nb">print</span><span class="p">(</span><span class="s">"Data :"</span><span class="p">,</span> <span class="n">data</span><span class="p">)</span>
<span class="k">def</span> <span class="nf">handle_comment</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">data</span><span class="p">):</span>
<span class="nb">print</span><span class="p">(</span><span class="s">"Comment :"</span><span class="p">,</span> <span class="n">data</span><span class="p">)</span>
<span class="k">def</span> <span class="nf">handle_entityref</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">name</span><span class="p">):</span>
<span class="n">c</span> <span class="o">=</span> <span class="nb">chr</span><span class="p">(</span><span class="n">name2codepoint</span><span class="p">[</span><span class="n">name</span><span class="p">])</span>
<span class="nb">print</span><span class="p">(</span><span class="s">"Named ent:"</span><span class="p">,</span> <span class="n">c</span><span class="p">)</span>
<span class="k">def</span> <span class="nf">handle_charref</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">name</span><span class="p">):</span>
<span class="k">if</span> <span class="n">name</span><span class="o">.</span><span class="n">startswith</span><span class="p">(</span><span class="s">'x'</span><span class="p">):</span>
<span class="n">c</span> <span class="o">=</span> <span class="nb">chr</span><span class="p">(</span><span class="nb">int</span><span class="p">(</span><span class="n">name</span><span class="p">[</span><span class="mi">1</span><span class="p">:],</span> <span class="mi">16</span><span class="p">))</span>
<span class="k">else</span><span class="p">:</span>
<span class="n">c</span> <span class="o">=</span> <span class="nb">chr</span><span class="p">(</span><span class="nb">int</span><span class="p">(</span><span class="n">name</span><span class="p">))</span>
<span class="nb">print</span><span class="p">(</span><span class="s">"Num ent :"</span><span class="p">,</span> <span class="n">c</span><span class="p">)</span>
<span class="k">def</span> <span class="nf">handle_decl</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">data</span><span class="p">):</span>
<span class="nb">print</span><span class="p">(</span><span class="s">"Decl :"</span><span class="p">,</span> <span class="n">data</span><span class="p">)</span>
<span class="n">parser</span> <span class="o">=</span> <span class="n">MyHTMLParser</span><span class="p">()</span>
</pre></div>
</div>
<p>Parsing a doctype:</p>
<div class="highlight-python3"><div class="highlight"><pre><span class="gp">>>> </span><span class="n">parser</span><span class="o">.</span><span class="n">feed</span><span class="p">(</span><span class="s">'<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" '</span>
<span class="gp">... </span> <span class="s">'"http://www.w3.org/TR/html4/strict.dtd">'</span><span class="p">)</span>
<span class="go">Decl : DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"</span>
</pre></div>
</div>
<p>Parsing an element with a few attributes and a title:</p>
<div class="highlight-python3"><div class="highlight"><pre><span class="gp">>>> </span><span class="n">parser</span><span class="o">.</span><span class="n">feed</span><span class="p">(</span><span class="s">'<img src="python-logo.png" alt="The Python logo">'</span><span class="p">)</span>
<span class="go">Start tag: img</span>
<span class="go"> attr: ('src', 'python-logo.png')</span>
<span class="go"> attr: ('alt', 'The Python logo')</span>
<span class="go">>>></span>
<span class="gp">>>> </span><span class="n">parser</span><span class="o">.</span><span class="n">feed</span><span class="p">(</span><span class="s">'<h1>Python</h1>'</span><span class="p">)</span>
<span class="go">Start tag: h1</span>
<span class="go">Data : Python</span>
<span class="go">End tag : h1</span>
</pre></div>
</div>
<p>The content of <tt class="docutils literal"><span class="pre">script</span></tt> and <tt class="docutils literal"><span class="pre">style</span></tt> elements is returned as is, without
further parsing:</p>
<div class="highlight-python3"><div class="highlight"><pre><span class="gp">>>> </span><span class="n">parser</span><span class="o">.</span><span class="n">feed</span><span class="p">(</span><span class="s">'<style type="text/css">#python { color: green }</style>'</span><span class="p">)</span>
<span class="go">Start tag: style</span>
<span class="go"> attr: ('type', 'text/css')</span>
<span class="go">Data : #python { color: green }</span>
<span class="go">End tag : style</span>
<span class="go">>>></span>
<span class="gp">>>> </span><span class="n">parser</span><span class="o">.</span><span class="n">feed</span><span class="p">(</span><span class="s">'<script type="text/javascript">'</span>
<span class="gp">... </span> <span class="s">'alert("<strong>hello!</strong>");</script>'</span><span class="p">)</span>
<span class="go">Start tag: script</span>
<span class="go"> attr: ('type', 'text/javascript')</span>
<span class="go">Data : alert("<strong>hello!</strong>");</span>
<span class="go">End tag : script</span>
</pre></div>
</div>
<p>Parsing comments:</p>
<div class="highlight-python3"><div class="highlight"><pre><span class="gp">>>> </span><span class="n">parser</span><span class="o">.</span><span class="n">feed</span><span class="p">(</span><span class="s">'<!-- a comment -->'</span>
<span class="gp">... </span> <span class="s">'<!--[if IE 9]>IE-specific content<![endif]-->'</span><span class="p">)</span>
<span class="go">Comment : a comment</span>
<span class="go">Comment : [if IE 9]>IE-specific content<![endif]</span>
</pre></div>
</div>
<p>Parsing named and numeric character references and converting them to the
correct char (note: these 3 references are all equivalent to <tt class="docutils literal"><span class="pre">'>'</span></tt>):</p>
<div class="highlight-python3"><div class="highlight"><pre><span class="gp">>>> </span><span class="n">parser</span><span class="o">.</span><span class="n">feed</span><span class="p">(</span><span class="s">'&gt;&#62;&#x3E;'</span><span class="p">)</span>
<span class="go">Named ent: ></span>
<span class="go">Num ent : ></span>
<span class="go">Num ent : ></span>
</pre></div>
</div>
<p>Feeding incomplete chunks to <a class="reference internal" href="#html.parser.HTMLParser.feed" title="html.parser.HTMLParser.feed"><tt class="xref py py-meth docutils literal"><span class="pre">feed()</span></tt></a> works, but
<a class="reference internal" href="#html.parser.HTMLParser.handle_data" title="html.parser.HTMLParser.handle_data"><tt class="xref py py-meth docutils literal"><span class="pre">handle_data()</span></tt></a> might be called more than once
(unless <em>convert_charrefs</em> is set to <tt class="docutils literal"><span class="pre">True</span></tt>):</p>
<div class="highlight-python3"><div class="highlight"><pre><span class="gp">>>> </span><span class="k">for</span> <span class="n">chunk</span> <span class="ow">in</span> <span class="p">[</span><span class="s">'<sp'</span><span class="p">,</span> <span class="s">'an>buff'</span><span class="p">,</span> <span class="s">'ered '</span><span class="p">,</span> <span class="s">'text</s'</span><span class="p">,</span> <span class="s">'pan>'</span><span class="p">]:</span>
<span class="gp">... </span> <span class="n">parser</span><span class="o">.</span><span class="n">feed</span><span class="p">(</span><span class="n">chunk</span><span class="p">)</span>
<span class="gp">...</span>
<span class="go">Start tag: span</span>
<span class="go">Data : buff</span>
<span class="go">Data : ered</span>
<span class="go">Data : text</span>
<span class="go">End tag : span</span>
</pre></div>
</div>
<p>Parsing invalid HTML (e.g. unquoted attributes) also works:</p>
<div class="highlight-python3"><div class="highlight"><pre><span class="gp">>>> </span><span class="n">parser</span><span class="o">.</span><span class="n">feed</span><span class="p">(</span><span class="s">'<p><a class=link href=#main>tag soup</p ></a>'</span><span class="p">)</span>
<span class="go">Start tag: p</span>
<span class="go">Start tag: a</span>
<span class="go"> attr: ('class', 'link')</span>
<span class="go"> attr: ('href', '#main')</span>
<span class="go">Data : tag soup</span>
<span class="go">End tag : p</span>
<span class="go">End tag : a</span>
</pre></div>
</div>
<p class="rubric">Footnotes</p>
<table class="docutils footnote" frame="void" id="id2" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<tr><td class="label"><a class="fn-backref" href="#id1">[1]</a></td><td>For backward compatibility reasons <em>strict</em> mode does not raise
exceptions for all non-compliant HTML. That is, some invalid HTML
is tolerated even in <em>strict</em> mode.</td></tr>
</tbody>
</table>
</div>
</div>
</div>
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<ul>
<li><a class="reference internal" href="#">20.2. <tt class="docutils literal"><span class="pre">html.parser</span></tt> — Simple HTML and XHTML parser</a><ul>
<li><a class="reference internal" href="#example-html-parser-application">20.2.1. Example HTML Parser Application</a></li>
<li><a class="reference internal" href="#htmlparser-methods">20.2.2. <tt class="docutils literal"><span class="pre">HTMLParser</span></tt> Methods</a></li>
<li><a class="reference internal" href="#examples">20.2.3. Examples</a></li>
</ul>
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