render should always remain pure. It’s a very bad practice to do side-effecty things in there, and calling setState is a big red flag; in a simple example like this it can work out okay, but it’s the road to highly unmaintainable components, plus it only works because the side effect is async. Instead, think … Read more
Probably the best way to handle this is with a factory function, which calls a private constructor. In Dart, private methods start with an underscore, and “additional” constructors require a name in the form ClassName.constructorName, since Dart doesn’t support function overloading. This means that private constructors require a name, which starts with an underscore (MyComponent._create … Read more
You do not need any special pipe. Angular 2 suppport optional field. You just need to add ? in your object {{ (data | async)?.name }} or {{(name | async)?}}
When you execute something synchronously, you wait for it to finish before moving on to another task. When you execute something asynchronously, you can move on to another task before it finishes. In the context of operating systems, this corresponds to executing a process or task on a “thread.” A thread is a series of … Read more
Though there are times when you may want to do things similar to what you’re trying to accomplish here, they are a rarity. So most people reading this, maybe even OP, may wish to restructure such that struct state and data used for a single async execution are different objects. To answer your question, yes … Read more
Updated answer: using async / await leads to cleaner code. Old code below. I’ve successfully solved this problem by combining the following elements: Mock out the promise and make it resolve immediately Make the test asynchronous by marking the test function async After simulating the click, wait until the next macrotask to give the promise … Read more
async/await is about asynchrony, whereas Parallel.ForEach is about parallelism. They’re related concepts, but not the same. Parallel.ForEach is used when you want to execute the same operation on all the items in a collection, in parallel, blocking the current thread until all operations have completed. async/await is used when the current operation can’t make any … Read more
The only time that you can wrap an async method in a synchronous one is when you don’t need to get a return value. For example if you want to disable the save button, save results to the server asynchronously and re-enable the save button when the job is done you can write it like … Read more
MSDN explains everything. I understand though that sometimes vanilla docs (particularly from MSDN) can be difficult to apply to your particular situation, so let’s go over your points. Question # 1: Is this assumption correct or the code below the await keyword is still executed? The code below the “await” keyword will only be executed … Read more
launch is used to fire and forget coroutine. It is like starting a new thread. If the code inside the launch terminates with exception, then it is treated like uncaught exception in a thread — usually printed to stderr in backend JVM applications and crashes Android applications. join is used to wait for completion of … Read more