Not really an answer for this OP I think, but rather than building a hash to detect matches (which for large arrays could be expensive), why not use a string?

Would this be a Cheap idiom? Update:Obviously not!:( See below.) Good for golf maybe> 

#! perl -sw
use strict;

my @array1= qw(1 83 90 120 140 300);
my @array2= qw(83 140);

my @array3 = grep{ local $"="\c1"; -1==index( "\c1@array2\c1", "\c1$_\
+c1") } @array1; 

print "@array3\n";

__END__
c:\test>205991
1 90 120 300

[download]
Cor! Like yer ring! ... HALO dammit! ... 'Ave it yer way! Hal-lo, Mister la-de-da. ... Like yer ring!

In reply to Re: subtract one array from another by BrowserUk
in thread subtract one array from another by Anonymous Monk

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