delay function
Wait for the duration specified in duration
.
This is not the same as sleep. This function does not block any asynchronous operations in the current Isolate.
Implementation
Future<void> delay(Duration duration) {
// Inform user if they provided a strange [duration].
//
// There is no need to throw, becaue [Future.delayed] also works with
// negative durations.
assert(
duration.isPositive,
"Delaying for a negative amount of time makes no sense.",
);
return Future.delayed(duration);
}