How to stop coroutines or functions

You're going about it the wrong way 'methinks' . Whack-a-mole is the classic example for a really small State Machine. I've got a 90% completed whack-a-something project over here. I'll try and strip it a bit

enum state_ { resting, movingUp, movingDown, knocked, coolDown }; state_ state;

 float t = 0;
 while(t < 1&&state == state_.movingUp)
 {
     yield return null;
     t += Time.deltaTime / moveUpTime;
     TR.position = Vector3.Lerp(start, topPosition, t);
 }
 if(state == state_.movingUp)
 SetState(4);//coolDown

So our moving up coroutine only does things if it's in that state while(t < 1&&state == state_.movingUp). When you click it for example, the GameManager just calls SetState(3) and that does something like:

IEnumerator Knocked()
{
    state = state_.knocked;
    // insert various logic bits here
    float t = 0;
    while(t < 1)
    {
        yield return null;
        t += Time.deltaTime / 0.55f;
        TR.position = Vector3.Lerp(start, bottomPosition, t);
    }
    SetState(0);//rest
}

Notice this doesn't have a state condition, since we want the mole to not be interupted while going back into it's hole.

Ofcourse you'll be checking for specific states and things within the state switcher (SetState) itself, before starting a coroutine. For example:

if(state == state_.resting)   // make sure the mole is not doing anything important
    StartCoroutine(MoveUp()); // start moving
else                          // if mole busy
        GM.GetMole()          // get another random mole from the array

The Project

Eureka! Thanks azzogat! I was doing some experimenting with while loops yesterday but Unity kept crashing. I think I found something that works well.

I'm not sold on the state machine. I haven't had any experience with enums yet, but after checking out your game, which is really cool, my plans are quite different. The code I have below is very different from what I was using (MoveObject script). If I keep going back to change things, I never get to move forward and learn from my mistakes. What I have now seems to work well so I'm going to stick with it.

var waitTime:float = 2.0; var moleVisible:boolean = false; var moleHit:boolean = false; var moleKilledSpeed = 5; var moleAliveSpeed = 1;

 moleVisible = true;
 StartCoroutine("MolePresents");

 // Mole ascends
 while (transform.position.y < 1){
     transform.Translate(Vector3.up * Time.deltaTime * moleAliveSpeed);
     yield;
 }
 
 // Mole waits
 yield WaitForSeconds (waitTime);
 
 // Mole descends
 while (transform.position.y > 0) {
     transform.Translate(Vector3.down * Time.deltaTime * moleAliveSpeed);
     yield;
 
 }
 
 Destroy (gameObject);
 

 while (transform.position.y > 0) {
     transform.Translate(Vector3.down * Time.deltaTime * moleKilledSpeed);
     yield;
 }
 
 // Remove object
 bMoleVisible = false;
 Destroy (gameObject);

 if (Input.GetKeyDown(KeyCode.KeypadEnter) && !moleHit) {
     // Recognize hit
     moleHit = true;
     
     // Adjust movement
     StopCoroutine("MolePresents");
     StartCoroutine("MoleKilled");
 }

}