And when i write something like that i usually change it to something like:
my %seen;
my @unique = grep {not $seen{$_}++} <FILE>;
chomp @unique;

[download]
Or something similar. It might not be the best way to do it, but it has one advantage...

It has nothing to do with using %_. It's mostly because i'm very wary of changing $_ in map, especially since i recently got very burned by attempting such a thing...

jynx

update: at prompting, i'll mention that one could write that as:

my (%seen, @unique);
chomp( @unique = grep {not $seen{$_}++} <FILE> );

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however, i think that would iterate twice as well. Then again there's that point about premature optimization... ;-)

Update 2: after doing a benchmark, i've found that the map solution is the fastest, followed by the one-line chomp and last is the two-liner. The one-liner is sufficiently fast enough that i would still prefer it, although for readability and maintainability i might still go with the two line version. To each their own...

Thanks demerphq for the learning experience... :-)

In reply to Re^6: Unique array w/o repeated elements and still keep the original order! by jynx
in thread Unique array w/o repeated elements and still keep the original order! by chuleto1

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