Advanced Coroutine Patterns

Real coroutines usually need more control than a single loop: waiting on conditions, nesting, and stopping cleanly.

IEnumerator SpawnWave(int count)
{
    for (int i = 0; i < count; i++)
    {
        Instantiate(enemyPrefab, RandomSpawnPoint(), Quaternion.identity);
        yield return new WaitForSeconds(1.5f);
    }
}

IEnumerator WaitForPlayerReady()
{
    yield return new WaitUntil(() => player.IsReady);
    Debug.Log("Player ready, starting match");
}

Useful yield instructions

Instruction	Waits for
`yield return null`	next frame
`yield return new WaitForSeconds(t)`	t seconds, scaled by `Time.timeScale`
`yield return new WaitForSecondsRealtime(t)`	t real seconds, ignores pause
`yield return new WaitUntil(() => condition)`	condition to become true
`yield return StartCoroutine(Other())`	a nested coroutine to finish

Stopping coroutines

Coroutine handle = StartCoroutine(SpawnWave(5));
...
StopCoroutine(handle);   // stop a specific one
StopAllCoroutines();      // stop everything running on this MonoBehaviour

A coroutine also stops automatically if the GameObject it's running on is destroyed or disabled.

Advanced Coroutine Patterns

Useful yield instructions

Stopping coroutines

📝 Advanced Coroutines Quiz