Pod::Elemental::Selectors - predicates for selecting elements


version 0.103005


Pod::Elemental::Selectors provides a number of routines to check for Pod::Elemental paragraphs with given qualities.


Selectors are predicates: they examine paragraphs and return either true or false. All the selectors have (by default) names like: s_whatever. They expect zero or more parameters to affect the selection. If these parameters are given, but no paragraph, a callback will be returned that will expect a paragraph. If a paragraph is given, the selector will return immediately.

For example, the s_command selector expects a parameter that can be the name of the command desired. Both of the following uses are valid:

  # create and use a callback:

  my $selector = s_command('head1');
  my @headers  = grep { $selector->($_) } @paragraphs;

  # just check a paragraph right now:

  if ( s_command('head1', $paragraph) ) { ... }

The selectors can be imported individually or as the -all group, and can be renamed with Sub::Exporter features. (Selectors cannot yet be curried by Sub::Exporter.)


  my $callback = s_blank;

  if( s_blank($para) ) { ... }

s_blank tests whether a paragraph is a Generic::Blank element.


  my $callback = s_flat;

  if( s_flat($para) ) { ... }

s_flat tests whether a paragraph does Pod::Elemental::Flat -- in other words, is content-only.


  my $callback = s_node;

  if( s_node($para) ) { ... }

s_node tests whether a paragraph does Pod::Elemental::Node -- in other words, whether it may have children.


  my $callback = s_command;
  my $callback = s_command( $command_name);
  my $callback = s_command(\@command_names);

  if( s_command(undef, \$para) ) { ... }

  if( s_command( $command_name,  \$para) ) { ... }
  if( s_command(\@command_names, \$para) ) { ... }

s_command tests whether a paragraph does Pod::Elemental::Command. If a command name (or a reference to an array of command names) is given, the tested paragraph's command must match one of the given command names.


Ricardo SIGNES <>


This software is copyright (c) 2020 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.