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:
- $p = HTML::PullParser->new( file => $file, %options )
- $p = HTML::PullParser->new( doc => \$doc, %options )
- 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 associating an argspec (as
defined in HTML::Parser) with the events you have an interest 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".
- $token = $p->get_token
- This method will return the next token found in the HTML document,
or "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.
- $p->unget_token( @tokens )
- 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.