Is it possible to animate int,double,enum inside animation window?

this simple script will expose field to unity inspector

Spoiler: Example code

Code (CSharp):

1. using UnityEngine;
2. using System.Collections;
3.  
4. public class Debug_AnimateIntEnum : MonoBehaviour {
5.  
6.     //can NOT animate
7.     public int myInt = 1;
8.     public uint myUInt = 3;
9.     public AnyEnum myEnum = AnyEnum.Default;
10.     public double myDouble;
11.  
12.     //can animate
13.     public float myFloat = 2f;
14.     public bool myBool = false;
15.     public Color myColor;
16.     public Texture myTexture;
17.     public AudioClip myAudioClip;
18.     public Vector3 myVector3;
19.     public Mesh myMesh;
20.     public RenderTexture myRenderTexture;
21.     public AnimationClip myAnimationClip;
22.  
23.  
24.     public enum AnyEnum
25.     {
26.         Default,
27.         A,
28.         B,
29.         C
30.     }
31. }
32.  

Only field that can be animated will turn to red

but int,uint,enum,double will not allow animate in animation window,
Is it by Unity's design? if Yes, I wonder the reason behind it,
because it is totally not reasonable to me.