use Perl

• And with Moose in Perl 5 (Score:1)

  by frew (9054)

  With Perl 5 that would look like either:
  
  package POC::TestAnnouncer;
  
  use Moose::Role;
  
  before test => sub {
    my $project = $_[1];
    announce-start-of('test', $project{name});
  };
  
  after test => sub {
    my $project = $_[1];
    announce-end-of('test', $project{name});
  };
  
  And then there's the more powerful around:
  
  package POC::TestAnnouncer;
  
  use Moose::Role;
  
  around test => sub {
    my $fn = shift;
    my $self = shift;
    my $project = $_[0];
    announce-start-of('test', $project{name});

  --
  --fREW
  http://blog.afoolishmanifesto.com
  • Re: (Score:1)

    by masak (6289)

    Thanks. I was only aware of how Moose did it to the extent that people come into the #perl6 channel sometimes and ask "what's the equivalent to Moose's before/after/around in Perl 6?" and we answer "[call|next][same|with]".

    (The "call-" methods are returning calls, and the "next-" methods are tailcalls. "-same" sends along the original arguments, and "-with" allows you to send new ones.)

    What's really neat, and what I still haven't quite gotten my head wrapped around, is that these four routines are used in t
    • Re: (Score:1)

      by masak (6289)

      Oh, huh, and I should probably add that mixins may look like they do a variant of wrapping in Perl 6, but they really work by creating an anonymous subclass to the class of the object, and re-blessing the object to that subclass. So, they work by inheritance, not wrapping.

      The fact that both of these use "callsame;" to delegate to the original routine means that I can use mixins and think they are wrappers, and they'll still behave as I expect. That's why I like the above unification.
      • Re: (Score:1)

        by perigrin (3495)

        Also playing about some I came up with something nearly identical using MooseX::Declare's syntax.

        
role POC::TestAnnouncer {
        use mro;

                method test ($project) {
            announce-start-of('test', $project{name});
            my $result = $self->maybe::next::method($project); # callsame
            announce-end-of('test', $result);
       
        • Re: (Score:1)

          by perigrin (3495)

          I mean $.callsame rather than .callsame. Thanks to TimToady and TiMBuS for clarifying things at least enough that I understand that much.
          • Re:And with Moose in Perl 5 (Score:1)

            by masak (6289) on 2010.07.08 5:11 (#72155) Homepage Journal

            Yes, it's $.callsame. See this post [perl.org] for a slightly deeper "why" answer.

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