As for the "obsolete" part, i used it --evidently badly-- as a synonym to "since there is no other code ... in the foreach block". Of course i was only refering to this snippet since next is invaluable in loop control. But i'm sure you knew that already. ;)

As for the grep gotcha, here is the situation. Given this code: 

my $line = "Alpha and some beta junk here";
my @keywords = qw(alpha beta gamma);

foreach (grep { $line =~ /$_/i } @keywords) {
    $_ = rand;
}

foreach (@keywords) { print "$_\n" }

[download]
We get when run: 
0.623870849609375
0.16607666015625
gamma

[download]
Grep aliases the current value of $_ to the original array element, and thus modifying it actually tampers our original data. It wasn't any special complication really, but has the potential to obfuscate a bug or two.

In reply to Re^5: Missing $ on loop variable by psychotic
in thread Missing $ on loop variable by superfrink

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