Higher-Order Functions

Then, for example, instead of this:

   170        foreach $x(0..2) {
   171           foreach $y(0..2) {         ##test for each square
   172              if ($move eq "$x$y") {
   173                 $squares->[$x][$y] = "x";   ## define array element for choice
   174              }
   175           }
   176        }

Use this:

        do_with_board(sub {
          if ($move eq "$_[0]$_[1]") {
             $squares->[$_[0]][$_[1]] = "x";   ## define array element for choice
          }
        });