in reply to Problem generating builder functions with Moose for inherited objects

I just had another look at the documentation and it turns out there is a meta method that you can use to do what you want: 

for my $attr ( $meta->get_all_attributes ) {
      print $attr->name, "\n";
  }

[download]
(from the MOP documentation). Prints out all attributes including inherited ones. To use it, I guess you should only define a BUILD method in the Parent class, where you replace your loop through the attributes by the above.

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Re^2: Problem generating builder functions with Moose for inherited objects
by Neighbour (Friar) on Sep 06, 2010 at 13:51 UTC
    That seems to work, thanks! :) That puts the BUILD method in the Parent class at this: 
    sub BUILD {
    my $self = shift;
    my $meta = $self->meta;
    print("BUILD called for " . __PACKAGE__ . "\n");
    no strict;
    foreach my $build_attribute ($meta->get_all_attributes) {
        my $build_attname = $build_attribute->name;
        print("Creating builder for attribute [" . $build_attname . "]
+\n");
        if (!defined *{__PACKAGE__ . '::_build_' . $build_attname}) {
            *{__PACKAGE__ . '::_build_' . $build_attname} = sub {
                my $self = shift;
                my $meta = $self->meta;
                my $attribute = $meta->find_attribute_by_name($build_a
+ttname);
                if (!defined $attribute) { Carp::confess("Error: Can't
+ find attribute [$build_attname]\n"); }
                my $type_name = $attribute->type_constraint->name;
                #if ($attribute->type_constraint->is_a_type_of("ArrayR
+ef[Any]")) { return []; }
                if ($type_name =~ /^ArrayRef/) { return []; }
                #elsif ($attribute->type_constraint->is_a_type_of("Has
+hRef[Any]")) { return {}; }
                elsif ($type_name =~ /^HashRef/) { return []; }
                elsif ($attribute->type_constraint->equals("Str")) { r
+eturn ""; }
                elsif ($attribute->type_constraint->is_a_type_of("Num"
+)) { return 0; }
                else { return undef };
            };
        } 
    }
    use strict;
}

    [download]
    Unfortunately, the 2 commented lines didn't work out, so I had to replace them with a ->name regex match.
[reply]
[d/l]
      You have the Moose::Meta::Attribute object already in $build_attribute in the outer loop, so you can do your test simply on that one: 
      $result = $build_attribute->type_constraint->is_a_type_of('ArrayRef') 
+? 'it's an ArrayRef' :'not an ArrayRef';

      [download]
      I just tried this in one of my Moose classes and it works for me that way.
[reply]
[d/l]

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