I didn't realize till after compiling an example that this was a rather old post, but I'll post it anyway. Here is an example of using attributes to added debug information to a sub (printing out its @_ before and after execution) as well as a way to wrap some errors/warnings around methods. Both of these use Hook::LexWrap to warp extra code around the function being attributed...attributized, attributated?</code>

use strict;
use warnings;
{  
   package tools;
   use Data::Dumper;
   use Hook::LexWrap;
   use Attribute::Handlers;
    sub UNIVERSAL::Debug :ATTR(CODE) {
            wrap $_[1], pre  => sub { pop; print Dumper({'Pre'  => \@_
+ })},
                        post => sub { pop; print Dumper({'Post' => \@_
+  })},
    }

    sub UNIVERSAL::Method :ATTR(CODE) {
            my ($package, $symbol, $referent, $attr, $data, $phase) = 
+@_;
            wrap $_[1], pre  => sub {  my $self = shift; 
                                       die "Must be used as a method" 
+unless ref($self) eq $package;
                                    };
    }
    
    

}
{
    package Test;
    sub method_test :Method {
        print "This should be called on a reference\n";
    }
}

package main;
sub foo : Debug { print "This is the end!\n"; return 123;};
foo(1,2,3);

my $x = bless {}, 'Test';
$x->method_test();

Test::method_test('hello');
__DATA__

$VAR1 = {
          'Pre' => [
                     1,
                     2,
                     3
                   ]
        };
This is the end!
$VAR1 = {
          'Post' => [
                      1,
                      2,
                      3
                    ]
        };
This should be called on a reference
Must be used as a method at attributes.pl line 16.
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