Originally posted here, on July 19, 2005, with the title "Is this a perl bug?", and signed by someone named "Ted":

Why does the following program print "Undefined!"? Shouldn't the subro
+utine
leave the value of $x alone? (I can understand it clobbering $_, but $
+x?)

#!/usr/bin/perl -w
use strict;
sub readZip() {
open FH, '/dev/null';
while (<FH>) { print "Got something!\n"; }
}

my $x = 'hi';
for ($x) { readZip(); }
print "Undefined!\n" unless defined $x;

(I'm using perl 5.6.1)
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