When you are doing things like this, you should consider using a hash instead of an array: 
my %hash = map { $_ => undef } @array;

# Add things to hash like this:

$hash{'a'} = undef;
$hash{'d'} = undef;

# Turn back into list with 'keys'

print join(',', sort keys %hash), "\n";

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In reply to Re: check element if inside an array by ctilmes
in thread check element if inside an array by Anonymous Monk

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