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

Good explanation, Abigail. I'm just curious, is there a good reason why while (<>) doesn't implicitely localize $_?

-- Hofmator

Replies are listed 'Best First'.
Re: Re: Re: When is $_ local and when is it not?
by chipmunk (Parson) on Jul 13, 2001 at 18:24 UTC
    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";

    [download]
    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";

    [download]
    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.
[reply]
[d/l]
[select]

In Section Seekers of Perl Wisdom