/ 
Pod-Abstract-0.14
River stage two • 5 direct dependents • 14 total dependents
/ Pod::Abstract

NAME

Pod::Abstract - Abstract document tree for Perl POD documents

SYNOPSIS

use Pod::Abstract;
use Pod::Abstract::BuildNode qw(node);

# Get all the first level headings, and put them in a verbatim block
# at the start of the document
my $pa = Pod::Abstract->load_filehandle(\*STDIN);
my @headings = $pa->select('/head1@heading');
my @headings_text = map { $_->pod } @headings;
my $headings_node = node->verbatim(join "\n",@headings_text);

$pa->unshift( node->cut );
$pa->unshift( $headings_node );
$pa->unshift( node->pod );

print $pa->pod;

DESCRIPTION

POD::Abstract provides a means to load a POD (or POD compatible) document without direct reference to it's syntax, and perform manipulations on the abstract syntax tree.

This can be used to support additional features for POD, to format output, to compile into alternative formats, etc.

PROCESSING MODEL

The intent with POD::Abstract is to provide a means to decorate a parse tree, rather than manipulate text, as a means to add features and functionality to POD based documenation systems.

If you wish to write modules that interact nicely with other POD::Abstract modules, then you should provide a POD::Abstract -> POD::Abstract translation. Leave any document element that your program is not interested in directly untouched in the parse tree, and if you have data that could be useful to other packages, decorate the parse tree with that data even if you don't see any direct way to use it in the output.

In this way, when you want one more feature for POD, rather than write or fork a whole translator, a single inline "decorator" can be added.

EXAMPLE

Suppose you are frustrated by the verbose list syntax used by regular POD. You might reasonably want to define a simplified list format for your own use, except POD formatters won't support it.

With Pod::Abstract you can right an inline filter to convert:

=begin list

* item 1
* item 2
* item 3

=end list

into:

=over

=item *

item 1

=item *

item 2

=item *

item 3

=back

This transformation can be simply performed on the document tree. If your formatter does not use Pod::Abstract, you can simply pipe out POD and use a regular formatter. If your formatter supports Pod::Abstract though, then you can feed in the syntax tree directly without having to re-serialise and parse the document.

POD SUPPORT

Pod::Abstract aims to support all POD rules defined in perlpodspec (even the ones I don't like), except for those directly related to formatting output, or which cannot be implemented generically.

COMPONENTS

Pod::Abstract is comprised of:

  • The parser, which loads a document tree for you.

    You should access this through Pod::Abstract, not directly

  • The document tree, which is the root node you are given by the parser. Calling pod on the root node should always give you back your original document.

    See Pod::Abstract::Node

  • Pod::Abstract::Path, the node selection expression language. This is generally called by doing <$node-select(PATH_EXP)>>.

  • The node builder, Pod::Abstract::BuildNode

METHODS

load_file

my $pa = Pod::Abstract->load_file( FILENAME );

Read the POD document in the named file. Returns the root node of the document.

load_filehandle

my $pa = Pod::Abstract->load_file( FH );

Load a POD document from the provided filehandle reference. Returns the root node of the document.

load_string

my $pa = Pod::Abstract->load_string( STRING );

Loads a POD document from a scalar string value. Returns the root node of the document.

AUTHOR

Ben Lilburne <bnej@mac.com>

COPYRIGHT AND LICENSE

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