This is not your CPAN's Meta

Posted on 2005-02-02 19:13:01-08 by theory

No, it's not part of the Meta namespace on CPAN. Class::Meta does class automation, data type validation, and provides an introdpection interface (metadata) for your classes.

So, what are you using Class::Meta for?

Cheers,

David

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Posted on 2005-02-28 22:10:28-08 by tkc in response to 13

Re: This is not your CPAN's Meta

I use Class::Meta. I'm considering making it a way of life... Thanks!

I've extended it a bit with a Constructor that calls _initialize when it's done. I've also created a MethodCheckParameter class which creates the actual method (like a constructor with create=>1). That method validates the paramters passed in and creates and instance of a special dynamically built class::meta to hold those parametets. It uses goto to make the final call which is nice because "caller" still works as expected.

Unfortunately, I had to fork Meta.pm as opposed to extend it because the add_method sub did not add the method to $classes->{<package>}->{build_meth_ord}. I filed a CR with bugs-class-meta@cpan.org (#11689) about this.

It works like this:

#!/usr/bin/perl -w use strict; package myclass; use TKC::Meta; use TKC::Meta::ConstructorInitialize; use TKC::Meta::MethodCheckParameters; use Class::Meta::Types::String qw(semi-affordance); BEGIN { my $cm = TKC::Meta->new(constructor_class => "TKC::Meta::ConstructorInitialize", method_class => "TKC::Meta::MethodCheckParameters", ); $cm->add_constructor(name=>"new", create=>1); my $meth = $cm->add_method(name=>"mymeth"); $meth->add_parameter(name=>'parameter', type=>'string'); $cm->build(); } sub _initialize { my ($this) = @_; print "INITIALIZE for: ",$this,"\n"; } sub _mymeth { my ($this, $params) = @_; print "THIS : ",$this, "\n"; print "PARAMS : ",$params, "\n"; print "CALLER : ",join(", ",caller), "\n"; print "PARAMETER: ",$params->parameter, "\n"; } 1;

When called by a little program in mytest.pl:

#!/usr/bin/perl -w use strict; use myclass; my $c = myclass->new(); $c->mymeth(parameter=> "this is a string"); exit(0);

You get the following output:

# perl mytest.pl INITIALIZE for: myclass=HASH(0x80f606c) THIS : myclass=HASH(0x80f606c) PARAMS : myclass::mymeth_parameters=HASH(0x81008a4) CALLER : main, mytest.pl, 6 PARAMETER: this is a string

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Posted on 2005-03-09 02:07:15-08 by theory in response to 165

Re: This is not your CPAN's Meta

Cool. Thanks for your patch. I've applied it and will release a new version soon.

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