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by gods
on Feb 11, 2000 at 00:06 UTC( #3333=superdoc: print w/replies, xml ) Need Help??
One possible reason for why while(<>) does not implicitly localize $_ as part of its magic is that sometimes you want to access the last value of $_ outside the loop. For example:
while (<>) { chomp; last if /\S/; } print "You said: $_\n";
If $_ were localized, you would have to copy the value to another variable:
my $in; while (local $_ = <>) { chomp; $in = $_, last if /\S/; } print "You said: $in\n";
Although it may just be as Abigail said, that foreach always assigns to a variable as part of the loop, whereas while can have anything in the conditional and (<>) is just a special case.

In reply to Re: Re: Re: When is $_ local and when is it not? by chipmunk
in thread When is $_ local and when is it not? by iakobski

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