in reply to truth in while condition

You haven't chomped the newline.

johngg@shiraz:~/perl/Monks$ perl -E '
$_ = qq{0\n};
say $_ ? q{True} : q{False};
chomp;
say $_ ? q{True} : q{False};'
True
False

[download]

Cheers,

JohnGG

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Re^2: truth in while condition
by TISON (Acolyte) on Sep 30, 2018 at 11:33 UTC
    Thanks for your reply! Sounds reasonable but what do you think about comment by LanX? It seems they are technically different.
[reply]
      Both are right, but it's a bit tricky to construct a while-condition doing a readline and exiting at false.

      I'd rather use an explicit last with condition inside the body.

      use strict;
use warnings;
use feature 'say';


while ( $_= <DATA>, chomp, $_) {
    say;
}

__DATA__
3
1
0
2

      [download]
      --> 
      3
1

      [download]

      (NB: Iterators don't necessarily loop over lines where they need to chomp, <update see here>)

      Cheers Rolf
      (addicted to the Perl Programming Language :)
      Wikisyntax for the Monastery FootballPerl is like chess, only without the dice

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[d/l]
[select]
        Get it! Again thanks to the help of both of you~
[reply]

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