Hello Monks,

I am construction a simple seen/lookup hash 
if($defined($seen{$key})){
 next;
}else{
 $seen{$key} = 1;
 next;
}

[download]
to get rid of duplicates. Anyway, as my hash-structure will get quite large, I need some tricks to reduce the size of the in-memory footprint. Strings lenghts are around 64-256. My idea was to compress data prior to looking it up in the $seen hash.

Now, is a gzipped version of a string a good idea as a Digest, compared to, let's say Digest::MD5 or Sha1? Or will I encounter lots of collisions? Anyone did that?

In reply to How good is gzip data as digest? by isync

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