Footnote to ikegami's reply. I found this, when I was hacking in some code on auto-pilot and ended up with my($_) instead of the intended local($_):

perl -e '@a=qw(a b c d e); for my $_ (@a){&f;print "$_\n"};sub f {$_=uc($_)}'

This indeed protects the caller from falling victim to a careless $_ use in a subroutine. Works in 5.10, but not in 5.8.

In reply to Re: Magical data modification using $_ by jakobi
in thread Magical data modification using $_ by Sewi

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