SUMMARY

Petal modifiers are snippets of code which are used to extend the expression engine capabilities. This test shows how to write your own modifiers.

API

The modifier API is very, very simple. It consists of two elements:

The package name

Your modifier should be called Petal::Hash::<SomeThing>, where <SomeThing> is the name that you want to give to your modifier.

For example, this modifier is called Petal::Hash::Test. Petal will automatically pick it the module up and assign it the 'test:' prefix.

    package Petal::Hash::Test;
    use warnings;
    use strict;

The method $class->process ($hash, $argument);

This class method will define the modifier in itself.

* $class is the package name of your modifier (which might come in handy if you're subclassing a modifier),

* $hash is the execution context, i.e. the objects and data which will 'fill' your template,

* $argument is whatever was after your modifier's prefix. For example, for the expression 'test:foo bar', $argument would be 'foo bar'.

In this test / tutorial we're going to write a modifier which uppercases a Petal expression.

  sub process
  {
      my $class    = shift;
      my $hash     = shift;
      my $argument = shift;
    
      return uc ($hash->get ($argument));
  }
  1;
  __END__

And that's it! Simple!

AUTHOR

Jean-Michel Hiver

This module is redistributed under the same license as Perl itself.