once you have assumed you have to use external storage, a sort based solution is not the most convenient anymore.

At least in theory, using a hash with on-disk storage (i.e. DB_File) is a better way with O(N) cost: 

my @data = qw(foo bar foo bar bar doz);

use DB_File;
use File::Temp qw(tempfile);

my ($fh, $fn) = tempfile(UNLINK => 1);
tie my %u, 'DB_File', $fn, O_RDWR, 0600;

$u{$_} = undef for @data;
@data = keys %u;

print "@data\n";

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In reply to Re: Saving an array to a disk file by salva
in thread Saving an array to a disk file by Anonymous Monk

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