Question

If I have an array and hash like these

#!/usr/bin/perl
use warnings;
use strict;
use Data::Dumper;

my @a = qw/a b c d e/;
my %h = (a => 1, b => 1, f => 1, g => 1);

and I would like to end up with @a containing all of the keys from %h, and no element in the array must appear more than once.

How can that be done, as exists doesn’t work on arrays?

Answer 1

You could make use of List::MoreUtils‘s uniq function:

use List::MoreUtils qw( uniq );

@a = uniq @a, keys %h;