While working on a recent project, I ran across a case where having a hash with multiple unordered keys would have been helpful. By multiple unordered keys I mean:

$hash{'keyA','keyB'} = "Some Value";
print $hash{'keyB', 'keyA'}; # prints "Some Value";

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After looking around on CPAN, I could not find a module that allowed this, and ended up writing my own. The code is here:

package Hash::MultiKey::Unordered;
use strict;
use warnings;

sub TIEHASH {
   my $class = shift;
   bless {}, $class;
}

sub FETCH {
   my $hash = shift;
   my $key = shift;
   return $hash->{ _fix($key)};
}
sub STORE {
   my $hash = shift;
   my $key = shift;
   my $value = shift;
   $hash->{_fix($key)} = $value;
}
sub DELETE { 
   my $hash = shift;
   my $key = shift;
   return delete $hash->{_fix($key)};
}
sub EXISTS { 
   my $hash = shift;
   my $key = shift;
   return exists $hash->{_fix($key)};
}
sub FIRSTKEY {
   my $hash = shift;
   keys %$hash;
   return each %$hash;
}
sub NEXTKEY {
   my $hash = shift;
   return each %$hash;
}
sub SCALAR {
   my $hash = shift;
   return scalar %$hash;
}

sub _fix {
   my $key = shift;
   my(@keys) = split /$;/, $key;
   @keys = sort @keys;
   $key = join $;, @keys;
   return $key;
}
1;

[download]

My questions are:

In reply to Multiple Unordered Hash Keys by neosamuri

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