Are you using an old version of Perl? There's an implicit defined in the scalar readline assignment; test it with B::Deparse yourself if you don't believe me:

$ perl -MO=Deparse
while (my $line = <>) {}
^D
while (defined(my $line = <ARGV>)) {
    ();
}

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In reply to Re^2: Passing a $Scaler into a while loop... by chromatic
in thread Passing a $Scaler into a while loop... by chinamox

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