MooseX::Types and coercion error

Question

As continue of this answer wow im fighting with the my own Moose "type library" - so trying to use "MooseX::Types".

Based on the above MooseX::Types docs, and "hoobs" comment to the above answer, I defined my own "types" as next:

package MyTypes;
use 5.016;
use Moose;
use MooseX::Types -declare => [qw( Dir File )];    
use MooseX::Types::Moose qw( Str );

use Path::Class::Dir;
use Path::Class::File;

class_type Dir, { class => 'Path::Class::Dir' };
coerce Dir, from Str, via { Path::Class::Dir->new($_) };

class_type File, { class => 'Path::Class::File' };
coerce File, from Str, via { Path::Class::File->new($_) };

1;

and used it in my package

package MyDir;
use Moose;
use warnings;
use MyTypes qw(Dir);    #to get the Dir type and its coercion

has 'path' => (
    is => 'ro',
    isa => Dir,      # Dir is defined in the package MyTypes
    required => 1,
);
1;

and tried with the next short script

use 5.016;
use warnings;
use MyDir;
my $d = MyDir->new(path => "/tmp");

Error:

Attribute (path) does not pass the type constraint because: Validation failed for 'MyTypes::Dir' with value /tmp (not isa Path::Class::Dir) at /Users/me/perl5/perlbrew/perls/perl-5.16.3/lib/site_perl/5.16.3/darwin-2level/Moose/Meta/Attribute.pm line 1279.
    Moose::Meta::Attribute::verify_against_type_constraint(Moose::Meta::Attribute=HASH(0x7f9e9b1c2618), "/tmp", "instance", MyDir=HASH(0x7f9e9b826bb8)) called at /Users/me/perl5/perlbrew/perls/perl-5.16.3/lib/site_perl/5.16.3/darwin-2level/Moose/Meta/Attribute.pm line 1266
    Moose::Meta::Attribute::_coerce_and_verify(Moose::Meta::Attribute=HASH(0x7f9e9b1c2618), "/tmp", MyDir=HASH(0x7f9e9b826bb8)) called at /Users/me/perl5/perlbrew/perls/perl-5.16.3/lib/site_perl/5.16.3/darwin-2level/Moose/Meta/Attribute.pm line 536
    Moose::Meta::Attribute::initialize_instance_slot(Moose::Meta::Attribute=HASH(0x7f9e9b1c2618), Moose::Meta::Instance=HASH(0x7f9e9b1c3588), MyDir=HASH(0x7f9e9b826bb8), HASH(0x7f9e9b826a98)) called at /Users/me/perl5/perlbrew/perls/perl-5.16.3/lib/site_perl/5.16.3/darwin-2level/Class/MOP/Class.pm line 525
    Class::MOP::Class::_construct_instance(Moose::Meta::Class=HASH(0x7f9e9b9e6990), HASH(0x7f9e9b826a98)) called at /Users/me/perl5/perlbrew/perls/perl-5.16.3/lib/site_perl/5.16.3/darwin-2level/Class/MOP/Class.pm line 498
    Class::MOP::Class::new_object(Moose::Meta::Class=HASH(0x7f9e9b9e6990), HASH(0x7f9e9b826a98)) called at /Users/me/perl5/perlbrew/perls/perl-5.16.3/lib/site_perl/5.16.3/darwin-2level/Moose/Meta/Class.pm line 284
    Moose::Meta::Class::new_object(Moose::Meta::Class=HASH(0x7f9e9b9e6990), HASH(0x7f9e9b826a98)) called at /Users/me/perl5/perlbrew/perls/perl-5.16.3/lib/site_perl/5.16.3/darwin-2level/Moose/Object.pm line 28
    Moose::Object::new("MyDir", "path", "/tmp") called at t.pl line 5

So, doesn't accept the 'Str' and don't do the coercion.

What is wrong in the above few lines? I'm pretty sure than it is really very small bug, because i followed the MooseX::Types docs (at least i hope) - but unable to find the error.

I'm starting be really hopeless with Moose, please HELP...

Ps: My goal is defining all my own "types" in one place (package) and use it everywhere where i need them with one single "use...".

Answer 1

You need to tell Moose that it's OK to use coercion on that attribute. You do this by adding coerce into the attribute definition:

has 'path' => (
    is => 'ro',
    isa => Dir,      # Dir is defined in the package MyTypes
    required => 1,
    coerce => 1,
    );