My js robot

hole.js

var Robot = function(robot) {};

Robot.prototype.onIdle = function(ev) {
  var robot = ev.robot;
  robot.ahead(20);
  robot.rotateCannon(10);
};

Robot.prototype.onWallCollision = function(ev) {
  ev.robot.turn(ev.bearing + 100);
}

Robot.prototype.onScannedRobot = function(ev) {
  var robot = ev.robot,
      loser = ev.scannedRobot,
      foe 	= loser.id != robot.id && loser.id != robot.parentId;
  
  if(!loser.parentId && foe) {
  	robot.fire();
  	robot.rotateCannon(-25);
  }
};

Robot.prototype.onHitByBullet = function(ev) {
  var robot = ev.robot; 
  robot.clone();
  if (robot.life < 40)
    robot.disappear();
};