What does the yield
keyword actually do in Dart?
yield
adds a value to the output stream of the surrounding async*
function. It's like return
, but doesn't terminate the function.
See https://dart.dev/guides/language/language-tour#generators
Stream asynchronousNaturalsTo(n) async* {
int k = 0;
while (k < n) yield k++;
}
When the yield statement executes, it adds the result of evaluating its expression to the stream. It doesn’t necessarily suspend (though in the current implementations it does).