KSURi has asked for the wisdom of the Perl Monks concerning the following question:

Hello, monks!

I'm writing a tool using a bunch of modern perl modules (MooseX::Declare, MooseX::Types, MooseX::MultiMethods). But it doesn't work: 

Subroutine My::Tool::method redefined at /usr/local/share/perl/5.10.0/
+MooseX/Method/Signatures.pm line 38.
Argument cannot be 'type' at /usr/local/share/perl/5.10.0/MooseX/Types
+/TypeDecorator.pm line 81
    MooseX::Types::TypeDecorator::new('MooseX::Types::TypeDecorator=HA
+SH(0xa3f6fe8)', 'type', 'mass', 'from', 'kg', 'to', 'g') called at /h
+ome/surikov/lib/My/Tool.pm line 12
    My::Tool::__ANON__('My::Tool=HASH(0x93cf9e0)', 'HASH(0x93cf760)') 
+called at t.pl line 56

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I'm definitely missing something, just don't understand what. Any suggestions?

PS: debugging with MooseX::Declare becomes quite difficult and takes a lot of time =(

I have defined my own data types in a separate package, like this: 
package My::Types;

use strict;
use warnings;

use MooseX::Types -declare => [qw(Measure MeasureType MeasureUnit some
+ other types)];
use MooseX::Types::Moose qw(Num Int Str);
use MooseX::Types::Structured qw(Dict);

use List::MoreUtils qw(any);

my @measure_types = qw(some data here);
my @measure_units = qw(and here);

subtype MeasureType,
    as Str,
    where   { my $measure_type = $_; any { $measure_type eq lc } @meas
+ure_types },
    message { 'Unknown measure type' };
subtype MeasureUnit,
    as Str,
    where   { my $measure_unit = $_; any { $measure_unit eq lc } @meas
+ure_units },
    message { 'Unknown measure unit' };
subtype Measure,
    as Dict[
        type   => MeasureType,
        from   => MeasureUnit,
        to     => MeasureUnit,
        amount => Num,
    ],
    message { 'Invalid Measure struct' };

# more subtypes goes here

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And here is the usage: 
class My::Tool {
# ...
    multi method convert(Measure $measure) {
        my $converter = My::Tool->new(
            type => $measure->{type},
            from => $measure->{from},
            to   => $measure->{to},
        );
        $converter->calculate($measure->{amount})
    }
# more 'convert' methods omitted
}

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Replies are listed 'Best First'.
Re: MooseX::Types::TypeDecorator error
by Anonymous Monk on Jul 16, 2009 at 13:13 UTC
    I can't seem to replicate that ; I get 
    Global symbol "$measure" requires explicit package name at test.pl lin
+e 41

    [download]
[reply]
[d/l]
      I can't replicate that too! Though below code is just simplified version of my code, it works fine: 
      use MooseX::Declare;

class Foo {
    use feature qw(say);

    use Data::Dumper;

    use MooseX::MultiMethods;
    use MooseX::Types -declare => [qw(Bar MyStr MyNum)];
    use MooseX::Types::Moose qw(Str Num);
    use MooseX::Types::Structured qw(Dict);

    BEGIN {
        subtype MyStr,
            as Str;
        subtype MyNum,
            as Num;

        subtype Bar,
            as Dict[
                string => MyStr,
                number => MyNum,
            ],
            message { 'Invalid Foo struct' };
    };

    multi method baz(Bar $barrr) {
        say'Bar';
        say Dumper $barrr
    }

    multi method baz(Str $string) {
        say 'Str';
        say Dumper $string;
    }
}

no Moose;
no MooseX::Declare;

1;

package main;

my $foo = Foo->new;
$foo->baz( { string => 'hello', number => 1.00, } );
$foo->baz( 'hello world' )

      [download]
[reply]
[d/l]
        Thanks. My problem is i'm missing MooseX::Declare because Devel-Declare-0.005007 won't compile on windows, sorry :)
[reply]

        You should put your MooseX-Types library into a separate file. The method signatures are parsed at compile time, and if they are defined in the same package, they are not declared yet.

        Ordinary morality is for ordinary people. -- Aleister Crowley
[reply]

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