Kotlinmedium

`launch` vs `async` — what’s the difference in coroutines?

Answer

`launch` starts a coroutine for side-effects and returns a `Job`. `async` returns a `Deferred<T>` for a result and you `await()` it; both should run inside a scope (structured concurrency).

coroutineScope {
  val a = async { 1 }
  val b = async { 2 }
  val sum = a.await() + b.await()
  println(sum)
}

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