According to the documentation Attribute::Handlers is "an excellent and intuitive interface through which to tie variables". I've tied a few variables in my time so I thought I'd give it a go.

But I think I'm misunderstanding it, as it doesn't give me the results I expect.

Here's a simple tied hash (that doesn't do anything useful)

#!/usr/bin/perl -w

package Tie::Hash::Test;
use Tie::Hash;
use vars qw(@ISA);
@ISA = 'Tie::StdHash';
sub TIEHASH {
  my $class = shift;

  my %self;
  @self{@_} = (undef) x @_;

  bless \%self, $class;
}

package main;

tie my %hash, 'Tie::Hash::Test', 'one', 'two', 'three';

print join(':', keys %hash), "\n";

[download]

Running this code gives the expected results of:

one:three:two

[download]

Here's the same tied hash using attributes:

#!/usr/bin/perl -w

package Tie::Hash::Test;
use Tie::Hash;
use Attribute::Handlers autotie => { __CALLER__::Test => __PACKAGE__ }
+;
use vars qw(@ISA);
@ISA = 'Tie::StdHash';
sub TIEHASH {
  my $class = shift;

  my %self;
  @self{@_} = (undef) x @_;

  bless \%self, $class;
}

package main;

my %hash : Test('one', 'two', 'three');

print join(':', keys %hash), "\n";

[download]

Running this code gives the result:

ARRAY(0x80f551c)

[download]

Which isn't quite what I expected.

Has anyone else tried this? Have you had better luck?

--
<http://www.dave.org.uk>

"The first rule of Perl club is you don't talk about Perl club."

In reply to autotie in Attribute Handlers by davorg

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