It sounds to me like you want Tie::Hash

my(%hash);
tie %hash, 'MyTiedHash';

$hash{a} = 'goodvalue'; # works
$hash{b} = 'badvalue'; # error

package MyTiedHash;
use Tie::Hash;
use Carp;
use base qw(Tie::StdHash);

sub STORE
{
   my($me,$key,$value) = @_;
   if($value eq 'goodvalue'){
      $me->{$key} = $value;
   }else{
      croak("$value not a good value for $key");
   }
   return 1;
}

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They say that time changes things, but you actually have to change them yourself.

—Andy Warhol

In reply to Re: How do I restrict a variable to a range of values? by JediWizard
in thread How do I restrict a variable to a range of values? by tphyahoo

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