NAME

Pod::Elemental::Transformer::List - transform :list regions into =over/=back to save typing

VERSION

version 0.102001

SYNOPSIS

By transforming your Pod::Elemental::Document like this:

  my $xform = Pod::Elemental::Transfomer::List->new;
  $xform->transform_node($pod_document);

You can then produce traditional Pod5 lists by using :list regions like this:

  =for :list
  * Doe
  a (female) deer
  * Ray
  a drop of golden sun

The behavior of list regions is slighly complex, and described below.

PERL VERSION

This library should run on perls released even a long time ago. It should work on any version of perl released in the last five years.

Although it may work on older versions of perl, no guarantee is made that the minimum required version will not be increased. The version may be increased for any reason, and there is no promise that patches will be accepted to lower the minimum required perl.

ATTRIBUTES

format_name

This attribute, which defaults to "list" is the region format that will be processed by this transformer.

LIST REGION PARSING

There are three kinds of lists: numbered, bulleted, and definition. Every list must be only one kind of list. Trying to mix list styles will result in an exception during transformation.

Lists can be written as a single paragraph beginning =for :list or a region marked off with =begin :list and =end :list. The content allowed in each of those two types is defined by the Pod specification but boils down to this: "for" regions will only be able to contain list markers and paragraphs of text, while "begin and end" regions can contain arbitrary Pod paragraphs and nested list regions.

All lists have a default indentlevel value of 4. Adding :over<n> to a =begin :list definition will result in that list having an indentlevel of n instead. (This functionality is not available for lists defined with =for :list.)

Ordinary paragraphs in list regions are scanned for lines beginning with list item markers (see below). If they're found, the list is broken into paragraphs and markers. Here's a demonstrative example:

  =for :list
  * Doe
  a deer,
  a female deer
  * Ray
  a drop of golden sun
  or maybe it's a golden
  drop of sun

The above is equivalent to

  =begin :list

  * Doe
  a deer,
  a female deer
  * Ray
  a drop of golden sun
  or maybe it's a golden
  drop of sun

  =end :list

It will be transformed into:

  =over 4

  =item *

  Doe

  a deer,
  a female deer

  =item *

  Ray

  a drop of golden sun
  or maybe it's a golden
  drop of sun

Which renders as:

  • Doe

    a deer, a female deer

  • Ray

    a drop of golden sun or maybe it's a golden drop of sun

rendering ends here

In other words: the * indicates a new bullet. The rest of the line is made into one paragraph, which will become the text of the bullet point when rendered. (Yeah, Pod is weird.) To continue the text of the bullet point on more than one line, start subsequent lines with white space.

  =for :list
  * this bullet line
    continues on a second line

Will be transformed into:

  =over 4

  =item *

  this bullet line continues on a second line

  =back

Which renders as:

  • this bullet line continues on a second line

rendering ends here

All subsequent lines without markers or leading white space will be kept together as one paragraph.

Asterisks mark off bullet list items. Numbered lists are marked off with "1." (or any number followed by a dot). Equals signs mark off definition lists. The markers must be followed by a space.

Here's a numbered list:

  =for :list
  1. bell
  2. book
  3. candle

The choice of number doesn't matter. The generated Pod =item commands will start with 1 and increase by 1 each time.

This is rendered as:

  1. bell

  2. book

  3. candle

rendering ends here

Definition lists are unusual in that the text on the line after a item marker will be used as the bullet, rather than the next paragraph. So this input:

  =begin :list

  = benefits

  There are more benefits than can be listed here.

  =end :list

Or this input:

  =for :list
  = benefits
  There are more benefits than can be listed here.

Will become the following output Pod:

  =over 4

  =item benefits

  There are more benefits than can be listed here

  =back

Which is rendered as:

benefits

There are more benefits than can be listed here

rendering ends here

If you want to nest lists, you have to make the outer list a begin/end region, like this:

  =begin :list

  * first outer item

  * second outer item

  =begin :list

  1. first inner item

  2. second inner item

  =end :list

  * third outer item

  =end :list

The inner list, above, could have been written as a compact "for" region.

AUTHOR

Ricardo SIGNES <cpan@semiotic.systems>

CONTRIBUTORS

  • Alex Peters <lxp@cpan.org>

  • David Golden <dagolden@cpan.org>

  • Justin Cook <jcook@cray.com>

  • Karen Etheridge <ether@cpan.org>

  • Ricardo Signes <rjbs@semiotic.systems>

  • Tomas Doran <bobtfish@bobtfish.net>

COPYRIGHT AND LICENSE

This software is copyright (c) 2022 by Ricardo SIGNES.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.