This is a somehow shorter version using the same technique but no named temporary array (it's more an exercise in concision than actually useful). 
use strict;

foreach my $d (sort keys %{{ map( ($_ => 1), <DATA>) }}  ) { 
    print $d;
}

__DATA__
a
B
a
B
dd

[download]
I wonder if there's a cleaner way to write the mapped expression.

In reply to Re: Re: Sorting Unique File Entries by l3nz
in thread Sorting Unique File Entries by Paulster2

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