I would be careful about using nested $_ variables in nested "for" loops. I encountered a bug in Perl 5.8.0, to be fixed in 5.8.1, that is detailed in Unbalanced string table refcount.

The better, and less buggy, approach is to use: 

for my $loop_outer (...
   for my $loop_innermost (...

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In reply to Re: Loop 'for' and '$_'. by Lhamo Latso
in thread Loop 'for' and '$_'. by nite_man

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