LeftPad in Perl

use feature qw(say);
sub leftPad {
  local($str, $paddedLength, $ch) = @_;
  if ($paddedLength <= length($str)) {
    return $str;
  }
  
  $ch = "." unless (defined($ch));
  if (length($ch) != 1) {
  	say "Invalid input";
    return $str;
  }
  
  $paddedLength = $paddedLength - length($str);
  return ($ch x $paddedLength) . $str;
}
say leftPad("1", 1);
say leftPad("2", 2);
say leftPad("3", 3);
say leftPad("4", 4);
say leftPad("5", 5);
say leftPad("hello", 7);
say leftPad("foo",  6);
say leftPad("foo", 3);
say leftPad("foobar", 3);
say leftPad("foo", 6, "?");