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

In reply to Re^3: truth in while condition by LanX
in thread truth in while condition by TISON

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