Back in 04/27/01 #76296 dvergin posted a solution to finding unique occurrences in a hash. It works beautifully but I can't figure how it works. 
my @ary = qw(a b c d d e b d);
my %hsh;
undef @hsh{@ary};
my @ary2 = keys %hsh;
print "@ary2\n";

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It's the line  undef @hsh{@ary} that I can't figure out. I need baby step explanations, I guess. Isn't @hsh and %hsh two completely different things? Thanks in advance. Pls refer to the what page # in the Camel book if possible.

In reply to hash slice by pglenski

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