# File: defect1.pl
use strict;
use warnings;

my $str = "  xyz";

$str =~ /^(\s*)/g or die;
print("match1: pos=", pos($str), "\n");

$str =~ /\G(\s*)/g or die;
print("match2: pos=", pos($str), "\n");

$str =~ /\G(\s*)/g or die;
print("match3: pos=", pos($str), "\n");