table of contents
Pod::Simple::PullParser(3perl) | Perl Programmers Reference Guide | Pod::Simple::PullParser(3perl) |
NAME¶
Pod::Simple::PullParser -- a pull-parser interface to parsing Pod
SYNOPSIS¶
my $parser = SomePodProcessor->new; $parser->set_source( "whatever.pod" ); $parser->run;
Or:
my $parser = SomePodProcessor->new; $parser->set_source( $some_filehandle_object ); $parser->run;
Or:
my $parser = SomePodProcessor->new; $parser->set_source( \$document_source ); $parser->run;
Or:
my $parser = SomePodProcessor->new; $parser->set_source( \@document_lines ); $parser->run;
And elsewhere:
require 5; package SomePodProcessor; use strict; use base qw(Pod::Simple::PullParser); sub run { my $self = shift; Token: while(my $token = $self->get_token) { ...process each token... } }
DESCRIPTION¶
This class is for using Pod::Simple to build a Pod processor -- but one that uses an interface based on a stream of token objects, instead of based on events.
This is a subclass of Pod::Simple and inherits all its methods.
A subclass of Pod::Simple::PullParser should define a "run" method that calls "$token = $parser->get_token" to pull tokens.
See the source for Pod::Simple::RTF for an example of a formatter that uses Pod::Simple::PullParser.
METHODS¶
- my $token = $parser->get_token
- This returns the next token object (which will be of a subclass of Pod::Simple::PullParserToken), or undef if the parser-stream has hit the end of the document.
- $parser->unget_token( $token )
- $parser->unget_token( $token1, $token2, ... )
- This restores the token object(s) to the front of the parser stream.
The source has to be set before you can parse anything. The lowest-level way is to call "set_source":
- $parser->set_source( $filename )
- $parser->set_source( $filehandle_object )
- $parser->set_source( \$document_source )
- $parser->set_source( \@document_lines )
Or you can call these methods, which Pod::Simple::PullParser has defined to work just like Pod::Simple's same-named methods:
- $parser->parse_file(...)
- $parser->parse_string_document(...)
- $parser->filter(...)
- $parser->parse_from_file(...)
For those to work, the Pod-processing subclass of Pod::Simple::PullParser has to have defined a $parser->run method -- so it is advised that all Pod::Simple::PullParser subclasses do so. See the Synopsis above, or the source for Pod::Simple::RTF.
Authors of formatter subclasses might find these methods useful to call on a parser object that you haven't started pulling tokens from yet:
- my $title_string = $parser->get_title
- This tries to get the title string out of $parser,
by getting some tokens, and scanning them for the title, and then
ungetting them so that you can process the token-stream from the
beginning.
For example, suppose you have a document that starts out:
=head1 NAME Hoo::Boy::Wowza -- Stuff B<wow> yeah!
$parser->get_title on that document will return "Hoo::Boy::Wowza -- Stuff wow yeah!". If the document starts with:
=head1 Name Hoo::Boy::W00t -- Stuff B<w00t> yeah!
Then you'll need to pass the "nocase" option in order to recognize "Name":
$parser->get_title(nocase => 1);
In cases where get_title can't find the title, it will return empty-string ("").
- my $title_string = $parser->get_short_title
- This is just like get_title, except that it returns just the modulename,
if the title seems to be of the form "SomeModuleName --
description".
For example, suppose you have a document that starts out:
=head1 NAME Hoo::Boy::Wowza -- Stuff B<wow> yeah!
then $parser->get_short_title on that document will return "Hoo::Boy::Wowza".
But if the document starts out:
=head1 NAME Hooboy, stuff B<wow> yeah!
then $parser->get_short_title on that document will return "Hooboy, stuff wow yeah!". If the document starts with:
=head1 Name Hoo::Boy::W00t -- Stuff B<w00t> yeah!
Then you'll need to pass the "nocase" option in order to recognize "Name":
$parser->get_short_title(nocase => 1);
If the title can't be found, then get_short_title returns empty-string ("").
- $author_name = $parser->get_author
- This works like get_title except that it returns the contents of the
"=head1 AUTHOR\n\nParagraph...\n" section, assuming that that
section isn't terribly long. To recognize a "=head1
Author\n\nParagraph\n" section, pass the
"nocase" option:
$parser->get_author(nocase => 1);
(This method tolerates "AUTHORS" instead of "AUTHOR" too.)
- $description_name = $parser->get_description
- This works like get_title except that it returns the contents of the
"=head1 DESCRIPTION\n\nParagraph...\n" section, assuming that
that section isn't terribly long. To recognize a "=head1
Description\n\nParagraph\n" section, pass the
"nocase" option:
$parser->get_description(nocase => 1);
- $version_block = $parser->get_version
- This works like get_title except that it returns the contents of the
"=head1 VERSION\n\n[BIG BLOCK]\n" block. Note that this does NOT
return the module's $VERSION!! To recognize a
"=head1 Version\n\n[BIG BLOCK]\n" section, pass the
"nocase" option:
$parser->get_version(nocase => 1);
NOTE¶
You don't actually have to define a "run" method. If you're writing a Pod-formatter class, you should define a "run" just so that users can call "parse_file" etc, but you don't have to.
And if you're not writing a formatter class, but are instead just writing a program that does something simple with a Pod::PullParser object (and not an object of a subclass), then there's no reason to bother subclassing to add a "run" method.
SEE ALSO¶
Pod::Simple
Pod::Simple::PullParserToken -- and its subclasses Pod::Simple::PullParserStartToken, Pod::Simple::PullParserTextToken, and Pod::Simple::PullParserEndToken.
HTML::TokeParser, which inspired this.
SUPPORT¶
Questions or discussion about POD and Pod::Simple should be sent to the pod-people@perl.org mail list. Send an empty email to pod-people-subscribe@perl.org to subscribe.
This module is managed in an open GitHub repository, <https://github.com/perl-pod/pod-simple/>. Feel free to fork and contribute, or to clone <git://github.com/perl-pod/pod-simple.git> and send patches!
Patches against Pod::Simple are welcome. Please send bug reports to <bug-pod-simple@rt.cpan.org>.
COPYRIGHT AND DISCLAIMERS¶
Copyright (c) 2002 Sean M. Burke.
This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.
This program is distributed in the hope that it will be useful, but without any warranty; without even the implied warranty of merchantability or fitness for a particular purpose.
AUTHOR¶
Pod::Simple was created by Sean M. Burke <sburke@cpan.org>. But don't bother him, he's retired.
Pod::Simple is maintained by:
- Allison Randal "allison@perl.org"
- Hans Dieter Pearcey "hdp@cpan.org"
- David E. Wheeler "dwheeler@cpan.org"
2024-05-30 | perl v5.38.2 |