This is, in effect, "hello, world" in the realm of coroutines. If you run this, you will see one message printed immediately and the other after a short delay.

There are five main elements when working with coroutines:

  1. A CoroutineScope, such as the GlobalScope that is used here

  2. A coroutine builder, such as the launch() function on GlobalScope

  3. Dispatchers, such as Dispatchers.Default and Dispatchers.Main

  4. suspend functions, for marking code that can be suspended safely so other code can run

  5. A CoroutineContext, such as the one created via withContext(), to change which dispatcher should be used for some code

All of these will be explored in upcoming lessons.

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A Conflated Channel A Fixed-Buffer Channel A Parallel Coroutine Sample A Sequential Coroutine Sample A Simple Channel A Simple Coroutine Sample A Simple Flow A Simple SharedFlow A Simple StateFlow A Zero-Buffer Channel async() BroadcastChannel cancelAndJoin() Canceling a Job Canceling a Parent Cancels Its Children Canceling and Cooperation catch() Channel and receive() Channels and Fan-out combine() Operator Contexts and Jobs Cooperation by Checking isActive Cooperation by Yielding debounce() Operator distinctUntilChanged() Operator distinctUntilChangedBy() Operator drop() Operator dropWhile() Operator filter() Operator filterIsInstance() Operator filterNot() Operator filterNotNull() Operator first() and Flow flattenConcat() Operator flattenMerge() Operator Flow Actions Flow onStart() flowOf() flowOn() Flows and Exceptions fold() Operator Hot Channels Via offer() invokeOnCompletion() Jobs and Parents Jobs Cancel When They Crash join() Lazy Coroutines map() Operator mapLatest() Operator mapNotNull() Operator Massively Parallel Coroutines MutableSharedFlow Replay Option Non-Cancellable Coroutines Parent Jobs Cancel When a Child Crashes promise() retry() retryWhen() runBlocking() sample() Operator scan() Operator single() and singleOrNull() Starting Lazy Coroutines StateFlow and Content Equality suspend Functions and Flows Suspending main() take() Operator takeWhile() Operator The Channel() Function TimeoutCancellationException Timeouts toList() and toSet() toList() for Channel withIndex() Operator withTimeoutOrNull() zip() Operator
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