You might try benchmarking the "do_map" case with: 
... keys %{ map { $_ => undef }  @array };
                       # not 0

[download]
I actually don't know how it would compare in terms of speed, but it would use a fair bit less memory. (I just checked the process size of "=> 0" vs. "=> undef", and the latter was about 1 MB smaller on a set of 100K hash keys.)

In reply to Re: Re: Unique Array Items by graff
in thread Unique Array Items by Anonymous Monk

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