NAME

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

DESCRIPTION

       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.

METHODS

   new
       Create a new filter with the specified arguments.

   require_params
       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.

   param
       Get the named param. Read only.

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

   run
       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).

AUTHOR

       Ben Lilburne <bnej@mac.com>

COPYRIGHT AND LICENSE

       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.