PHP yield without for?

It doesn’t require a loop. This works:

function foo() {
   yield 1;
   yield 2;
   yield 3;
} 

One reason to use this is to use it as a similar feature as ‘await’ in Javascript.

It’s possible for example to build an async framework that uses yield for this purpose:

function foo() {
   $response = yield asyncHttpRequest('GET', 'http://blabla');
}

This specific example is fictional, but it’s possible (and has been done).

I made such an async library. Docs here: https://sabre.io/event/coroutines/

There’s better maintained/more popular libraries out there though.