/**
* Executes the emitter coroutine.
*/
private function start()
{
Loop\queue(function () {
// Asynchronously start the observable.
if (null === $this->emitter) {
return;
}
/**
* Emits a value from the observable.
*
* @coroutine
*
* @param mixed $value If $value is an instance of \Icicle\Awaitable\Awaitable, the fulfillment value is
* used as the value to emit or the rejection reason is thrown from this coroutine. If $value is an
* instance of \Generator, it is used to create a coroutine which is then used as an awaitable.
*
* @return \Generator
*
* @resolve mixed The emitted value (the resolution value of $value)
*
* @throws \Icicle\Observable\Exception\CompletedError If the observable has been completed.
* @throws \Icicle\Observable\Exception\BusyError If the observable is still busy emitting a value.
*/
$emit = function ($value = null) : \Generator {
return $this->queue->push($value);
};
try {
$generator = ($this->emitter)($emit);
if (!$generator instanceof Generator) {
throw new UnexpectedTypeError('Generator', $generator);
}
$this->coroutine = new Coroutine($generator);
$this->coroutine->done(function ($value) {
$this->queue->complete($value);
}, function (Throwable $exception) {
$this->queue->fail($exception);
});
} catch (Throwable $exception) {
$this->queue->fail(new InvalidEmitterError($this->emitter, $exception));
}
$this->emitter = null;
});
}
