Pod::Abstract::Filter - Generic Pod-in to Pod-out filter.

This is a superclass for filter modules using Pod::Abstract. Subclasses should override the filter sub. Pod::Abstract::Filter classes in the Pod::Abstract::Filter namespace will be used by the paf utility.

To create a filter, you need to implement:

filter

Takes a Pod::Abstract::Node tree, and returns either another tree, or a string. If a string is returned, it will be re-parsed to be input to any following filter, or output directly if it is the last filter in the list.

It is recommended your filter method produce a Node tree if you are able to, as this will improve interoperability with other Pod::Abstract based software.

require_params

If you want positional arguments following your filter in the style of:

 paf find [thing] Pod::Abstract

then override require_params to list the named arguments that are to be accepted after the filter name.

Create a new filter with the specified arguments.

Override to return a list of parameters that must be provided. This will be accepted in order on the command line, unless they are first set using the -flag=xxx notation.

Get the named param. Read only.

Stub method. Does nothing, just returns the original tree.

Run the filter. If $arg is a string, it will be parsed first. Otherwise, the Abstract tree will be used. Returns either a string or an abstract tree (which may be the original tree, modified).

Ben Lilburne <bnej@mac.com>

Copyright (C) 2009 Ben Lilburne

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