move-as-coord.js

function moveAsCoord(move, head) {
  switch (move) {
    case 'up':
      return {x: head.x, y: head.y-1}; 
    case 'down':
      return {x: head.x, y: head.y+1};
    case 'left':
      return {x: head.x-1, y: head.y}; 
    case 'right':
      return {x: head.x+1, y: head.y};	
  }
}