Yeah, but I don't like it. I don't like assigning X to itself like the example does. I'd prefer a slightly long-winded approach: 
$hash{$_} = $otherhash{$_} for grep !exists $hash{$_}, keys %otherhash
+;

[download]
Or: 
{
  my @new_keys = grep !exists $hash{$_}, keys %otherhash;
  @hash{@new_keys} = @otherhash{@new_keys};
}

[download]
_____________________________________________________
Jeff japhy Pinyan, P.L., P.M., P.O.D, X.S.: Perl, regex, and perl hacker
How can we ever be the sold short or the cheated, we who for every service have long ago been overpaid? ~~ Meister Eckhart

In reply to Re^3: Concerning hash operations (appending, concatenating) by japhy
in thread Concerning hash operations (appending, concatenating) by RazorbladeBidet

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