I agree with sauoq.

Just want to add a little bit for people new to Perl, so that they are less confused. In general, to use and not to use "defined" are not logically equivalent, as Perl evulates both undef and empty string to false, but with defined, it only evaluates undef to false: (but in the particular case of assignment from <> to scalar, see sauoq's original post for explanation)

Try this code by uncommenting one of those two while lines, and observe the result:

use strict;
use warnings;

my $str = "";
#while (defined($str)) {#caution: this is different from what sauoq ha
+d, as this is not an assignment from <>
#while ($str) {
    print "inside while loop\n";
}

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In reply to Re: To Kill a Meme: while(defined($line = <>)) by pg
in thread To Kill a Meme: while(defined($line = <>)) by sauoq

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