in reply to hashes: testing for the presence of a key

See 'perldoc -f exists'. That will tell you if a given scalar is a key in an array.

What do you mean by "extract", though? Do you mean that you want the array to be altered?

@array = grep { ! exists $hash{$_} } @array;

Update: That first sentence should end with "in a hash". Thanks to VSarkiss for the typo catch :)

Cheers,
Ovid

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