Future Perl

This is mostly stuff I’ve gathered from this talk and updated slightly.

First off, have you ever tried to teach a programmer perl? I have. Note this:

sub foo {
   my ($self, $bar,$baz) = @_;
   #...
}

# or often
sub station {
   my $self = shift;
   #...
}

The following is more palatable to most coders (also I like it better:)

use Method::Signatures::Simple;
method foo($bar, $baz) {
   #...
}

method station {
   #...
}

That’s right, no fiddling with @_ at all. Sweet! Also note: this is not implemented with sketchy source filters. It’s quite robust. There is also MooseX::Method::Signatures (and MooseX::Declare which uses that) which can do even more, like defining named and optional params and type constraints.

I’ve already mentioned IO::All, so I’ll just say that it’s been endorsed by Matthew S. Trout, so you don’t have to tell me that the Right Way is to use some crufty C based interface or some weird old perl module that has capital letters in the functions and method parameters.

Next up, Moose::Autobox. I’ve also mentioned autobox, which this module uses, but Moose::Autobox goes further and defines some roles that your classes can also use to make them act like arrays etc. I wouldn’t be surprised if DBIx::Class 0.09x used some of these roles. Anyway, here’s a real example:

use Method::Signature::Simple;
use Moose::Autobox;

method criticisms {
   return {
      data  => $self->files_criticized->values->map(sub { @{ $_->{criticisms} } })
   };
}

Not quite Perl 6/Ruby, but still much clearer than the original (at least to this function programmer!)

And the of course there is the recently released (four months ago!) TryCatch. I haven’t used this module at all, but I look forward to it. It could really streamline some of the stuff we do at work.

Lastly, CLASS is a tiny nicety. All it does is replace __PACKAGE__ with CLASS; the code looks cleaner with it and it’s certainly shorter and easier to type.

I think we’ll be seeing a lot more of this kind of stuff in the near future. Devel::Declare seems to have mostly matured, so these modules will probably continue to crop up.

Anyway, woohoo! The future!

Posted Thu, May 7, 2009

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