well this my %intersection = grep $set1{$_}, keys %set2; is wrong, you're assigning a list of keys to a hash.

and you missed so many points from my post that I assume that you only read the headings... or how do you want to intersect sets of objects like this?

Cheers Rolf

In reply to Re^2: Using hashes for set operations... by LanX
in thread Using hashes for set operations... by LanX

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