HTML::PullParser - Alternative HTML::Parser interface
use HTML::PullParser;
$p = HTML::PullParser->new(file => "index.html", start => 'event, tagname, @attr', end => 'event, tagname', ignore_elements => [qw(script style)], ) || die "Can't open: $!"; while (my $token = $p->get_token) { #...do something with $token }
The HTML::PullParser is an alternative interface to the HTML::Parser class. It basically turns the HTML::Parser inside out. You associate a file (or any IO::Handle object or string) with the parser at construction time and then repeatedly call $parser->get_token to obtain the tags and text found in the parsed document.
The following methods are provided:
A HTML::PullParser
can be made to parse from either a file or a
literal document based on whether the file
or doc
option is
passed to the parser's constructor.
The file
passed in can either be a file name or a file handle
object. If a file name is passed, and it can't be opened for reading,
then the constructor will return an undefined value and $! will tell
you why it failed. Otherwise the argument is taken to be some object
that the HTML::PullParser
can read() from when it needs more data.
The stream will be read() until EOF, but not closed.
A doc
can be passed plain or as a reference
to a scalar. If a reference is passed then the value of this scalar
should not be changed before all tokens have been extracted.
Next the information to be returned for the different token types must
be set up. This is done by simply assosiating an argspec (as defined
in HTML::Parser) with the events you have an interrest in. For
instance, if you want start
tokens to be reported as the string
'S'
followed by the tagname and the attributes you might pass an
start
-option like this:
$p = HTML::PullParser->new( doc => $document_to_parse, start => '"S", tagname, @attr', end => '"E", tagname', );
At last other HTML::Parser
options, like ignore_tags
, and
unbroken_text
, can be passed in. Note that you should not use the
event_h options to set up parser handlers. That would confuse the
inner logic of HTML::PullParser
.
undef
at the end of the document. The token is returned as an
array reference. The content of this array match the argspec set up
during HTML::PullParser
construction.
If you find out you have read too many tokens you can push them back, so that they are returned again the next time $p->get_token is called.
The 'eg/hform' script shows how we might parse the form section of HTML::Documents using HTML::PullParser.
HTML::Parser, HTML::TokeParser
Copyright 1998-2001 Gisle Aas.
This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.