I am writing an object to act as a set (as in the Computer Science description). It main requirement is to be as slim and fast as possible. I have used a hash as the backing data structure because this allows me to enforce the 'no duplicates' property of sets.

So to add an element to the hash I just map it to undef as such:

$set{$item} = undef;

One thing I want to do is combine two sets. Obviously this could be a real performance bottleneck and due to its intended use it is essential I combine the two backing hashes as fast as possible. Obviously I could use:

foreach $key (keys %set1) {
  $set2{$key} = undef;
}

[download]

Is this the quickest way I can manage... or is there potentially a faster technique that anyone knows?

Thanks...

____________
Arun

In reply to Fast Way to Combine Two Hashes by arunhorne

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