Wouldn't it be better if the role names matched the ref? I.e. CODE,ARRAY,HASH,REGEX ? And could I see the patch? Just curiousity to see how something like that would be implemented, seems easy enough to implement in perl if you wanted and import it in.

Here is my stab. I went with a DOES sub returning a list of roles that an object does, makes it easy to make them inheritable...(i.e. 

sub DOES { qw/log print/, shift->SUPER::DOES() }</code). Realy just fo
+r my fun and amusment. ;)  /me goes off to investigate the various ro
+les modules</p>
<code>
use strict;
use warnings;

use Test::More qw/no_plan/;

{ package UNIVERSAL;
  sub does {
    return 1 if ref $_[0] eq $_[1];
    #if ( eval qq/"@" . ref($_[0]) . "::DOES"/;
    if (UNIVERSAL::isa($_[0], 'UNIVERSAL') ) {
      if ($_[0]->can('DOES')) { 
        return 1 if grep { $_[1] eq $_ } $_[0]->DOES();
      } else {
        return 1 if $_[0]->isa($_[1]);       
      }
    }
    return 0;
  }
}

sub say {print @_, "\n";}
    
{package Foo};

is(UNIVERSAL::does(sub{},'CODE'),  1, 'Code Ref');          
is(UNIVERSAL::does(qr//,'Regexp'), 1, 'Regex');            # return tr
+ue
is(UNIVERSAL::does([],'ARRAY')   , 1, 'Array')  ;             # return
+ true
is(UNIVERSAL::does([],'The::Funky::Chicken'),0 , 'Bad Class name') ;# 
+return false
is(UNIVERSAL::does([],'UNIVERSAL'),0, 'Array isn\'t Univeral')  ;     
+   # return false

@Bar::ISA=qw(Foo);
is(UNIVERSAL::does('Bar', 'Foo'), 1, 'Bar does Foo');          # retur
+n true

{package Bang;
   @Bang::ISA=qw(Foo UNIVERSAL);
   sub DOES { qw(test) };
}
is(Bang->does('Foo'), 0, 'Bang doesn\'t Foo');                        
+ # return false


{ package A;
  sub DOES { qw/this or that/ };
}

{ package B;
  @B::ISA = qw/A/;
  sub DOES { qw/other/ };  
}

#B->test();
is(A->does('this') , 1, 'A does this');   # true
is(B->does('that') , 0, 'B doesn\'t do that');    # false
is(B->does('other'), 1, 'B does other');   # true

[download]

___________
Eric Hodges

In reply to Re^3: I don't understand UNIVERSAL::DOES() by eric256
in thread I don't understand UNIVERSAL::DOES() by rlb3

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