using UnityEngine;

sealed class TestDoubleQuesionMark : MonoBehaviour {
    void OnEnable () {
        Test<BoxCollider> ();
        Test<SphereCollider> ();
        Test<CharacterController> ();
        Test<Rigidbody> ();
    }

    void Test<T> () where T : Component {
        Debug.Log (string.Format ("TEST: {0}", typeof (T).Name));
        var component = GetComponent<T> () ?? gameObject.AddComponent<T> ();
    }

    void Test1<T> () where T : Component {
        Debug.Log (string.Format ("TEST: {0}", typeof (T).Name));
        var component = GetComponent<T> ();
        if (component == null) {
            component = gameObject.AddComponent<T> ();
        }
    }
}