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Updated: Wednesday, July 27, 2022
 
 

HTML::HeadParser (3)

Name

HTML::HeadParser - Parse <HEAD> section of a HTML document

Synopsis

require HTML::HeadParser;
$p = HTML::HeadParser->new;
$p->parse($text) and  print "not finished";

$p->header('Title')          # to access <title>....</title>
$p->header('Content-Base')   # to access <base href="http://...">
$p->header('Foo')            # to access <meta http-equiv="Foo" content="...">
$p->header('X-Meta-Author')  # to access <meta name="author" content="...">
$p->header('X-Meta-Charset') # to access <meta charset="...">

Description

User Contributed Perl Documentation                        HTML::HeadParser(3)



NAME
       HTML::HeadParser - Parse <HEAD> section of a HTML document

SYNOPSIS
        require HTML::HeadParser;
        $p = HTML::HeadParser->new;
        $p->parse($text) and  print "not finished";

        $p->header('Title')          # to access <title>....</title>
        $p->header('Content-Base')   # to access <base href="http://...">
        $p->header('Foo')            # to access <meta http-equiv="Foo" content="...">
        $p->header('X-Meta-Author')  # to access <meta name="author" content="...">
        $p->header('X-Meta-Charset') # to access <meta charset="...">

DESCRIPTION
       The "HTML::HeadParser" is a specialized (and lightweight)
       "HTML::Parser" that will only parse the <HEAD>...</HEAD> section of an
       HTML document.  The parse() method will return a FALSE value as soon as
       some <BODY> element or body text are found, and should not be called
       again after this.

       Note that the "HTML::HeadParser" might get confused if raw undecoded
       UTF-8 is passed to the parse() method.  Make sure the strings are
       properly decoded before passing them on.

       The "HTML::HeadParser" keeps a reference to a header object, and the
       parser will update this header object as the various elements of the
       <HEAD> section of the HTML document are recognized.  The following
       header fields are affected:

       Content-Base:
           The Content-Base header is initialized from the <base href="...">
           element.

       Title:
           The Title header is initialized from the <title>...</title>
           element.

       Isindex:
           The Isindex header will be added if there is a <isindex> element in
           the <head>.  The header value is initialized from the prompt
           attribute if it is present.  If no prompt attribute is given it
           will have '?' as the value.

       X-Meta-Foo:
           All <meta> elements containing a "name" attribute will result in
           headers using the prefix "X-Meta-" appended with the value of the
           "name" attribute as the name of the header, and the value of the
           "content" attribute as the pushed header value.

           <meta> elements containing a "http-equiv" attribute will result in
           headers as in above, but without the "X-Meta-" prefix in the header
           name.

           <meta> elements containing a "charset" attribute will result in an
           "X-Meta-Charset" header, using the value of the "charset" attribute
           as the pushed header value.

           The ':' character can't be represented in header field names, so if
           the meta element contains this char it's substituted with '-'
           before forming the field name.

METHODS
       The following methods (in addition to those provided by the superclass)
       are available:

       $hp = HTML::HeadParser->new
       $hp = HTML::HeadParser->new( $header )
           The object constructor.  The optional $header argument should be a
           reference to an object that implement the header() and
           push_header() methods as defined by the "HTTP::Headers" class.
           Normally it will be of some class that is a or delegates to the
           "HTTP::Headers" class.

           If no $header is given "HTML::HeadParser" will create an
           "HTTP::Headers" object by itself (initially empty).

       $hp->header;
           Returns a reference to the header object.

       $hp->header( $key )
           Returns a header value.  It is just a shorter way to write
           "$hp->header->header($key)".

EXAMPLE
        $h = HTTP::Headers->new;
        $p = HTML::HeadParser->new($h);
        $p->parse(<<EOT);
        <title>Stupid example</title>
        <base href="http://www.linpro.no/lwp/">
        Normal text starts here.
        EOT
        undef $p;
        print $h->title;   # should print "Stupid example"


ATTRIBUTES
       See attributes(7) for descriptions of the following attributes:


       +---------------+----------------------------------+
       |ATTRIBUTE TYPE |         ATTRIBUTE VALUE          |
       +---------------+----------------------------------+
       |Availability   | library/perl-5/html-entities-532 |
       +---------------+----------------------------------+
       |Stability      | Volatile                         |
       +---------------+----------------------------------+

SEE ALSO
       HTML::Parser, HTTP::Headers

       The "HTTP::Headers" class is distributed as part of the libwww-perl
       package.  If you don't have that distribution installed you need to
       provide the $header argument to the "HTML::HeadParser" constructor with
       your own object that implements the documented protocol.

COPYRIGHT
       Copyright 1996-2001 Gisle Aas. All rights reserved.

       This library is free software; you can redistribute it and/or modify it
       under the same terms as Perl itself.



NOTES
       Source code for open source software components in Oracle Solaris can
       be found at https://www.oracle.com/downloads/opensource/solaris-source-
       code-downloads.html.

       This software was built from source available at
       https://github.com/oracle/solaris-userland.  The original community
       source was downloaded from
       https://cpan.metacpan.org/authors/id/G/GA/GAAS/HTML-Parser-3.72.tar.gz.

       Further information about this software can be found on the open source
       community website at https://metacpan.org/pod/HTML::Entities.



perl v5.32.0                      2013-10-21               HTML::HeadParser(3)