Or even (golf alert): perl -ne '${$_}||=print' file (although it's not strict compliant, and breaks if strings have NULLs in them).

$_="goto+F.print+chop;\n=yhpaj";F1:eval

In reply to RE: RE: RE (tilly) 1: remove duplicate lines from input file by japhy
in thread remove duplicate lines from input file by AltBlue

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