Err, okay, my answer, short and sweet: use a hash and array slices: 
my @a=(1 .. 2);
my @b=(2 .. 3);
my %c;
@c{@a,@b}=(@a,@b);
warn "Duplicates exist!" if scalar @c{@a,@b} != (@a+@b);

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Of course, in this instance you don't want the last line - instead you'd probably want something like: 
my @d=keys %c;

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...which will be out-of-order, but guaranteed duplicate free.

In reply to Re: How do I find if an array has duplicate elements, if so discard it? by rjimlad
in thread How do I find if an array has duplicate elements, if so discard it? by toddprof

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