$str = 'ABC';
   pos($str) = 1;
   while (/.\G/g) {
     print $&;
   }


##</code><code>##

   use warnings;
   $str = 'ABC';
   pos($str) = 1;
   while ($str=~/.\G/g) {
     print $&;
   }


##</code><code>##

   print pos($str);  #line6
   while ($str=~/.\G/g) {
     print $&;
   }


##</code><code>##

   
use warnings;
$str = 'ABC';
print pos($str);
#   pos($str) = 1;
while ($str=~/.\G/g) {
     print $&;
}


##</code><code>##

Use of uninitialized value in print at /home/lanx/B/PL/PM/re_escG.pl line 2.
Use of uninitialized value $& in print at /home/lanx/B/PL/PM/re_escG.pl line 5.