Manpages - HTML_HeadParser.3pm

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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 = :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”

SEE ALSO

HTML::Parser, :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.

Author: dt

Created: 2022-02-20 Sun 16:24