var enemies = this.getEnemies();
var nearestEnemy = null;
var i = 0;

while(i < enemies.length) {
    var enemyDist = this.distanceTo(enemies[i]);
    if(nearestEnemy === null || this.distanceTo(nearestEnemy)  > enemyDist){
        nearestEnemy = enemies[i];
    }
    ++i;
}
return nearestEnemy;