Just curious... would you get the "Out of memory!" result if you simply did this instead of the "uniq" call (other things being equal up to this point): 
  my @uvery_big_array = @very_big_array;

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In any case, since one way or another you'll need to sacrifice some runtime to economize on memory usage, a last resort might be to simply save @very_big_array to a disk file, run unix "sort -u" on that, and read it back in to the same array variable. (Obviously not an attractive option if portability is an issue, but if this is just an "in-shop" process, unix "sort" has been ported to every popular OS.)

In reply to Re: Howto Avoid Memory Problem in List::MoreUtils by graff
in thread Howto Avoid Memory Problem in List::MoreUtils by Anonymous Monk

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