/**
* Resume execution of a suspended coroutine by passing it an exception.
*
* @param StrandInterface $strand The strand that is executing the coroutine.
* @param Exception $exception The exception to send to the coroutine.
*/
public function resumeWithException(StrandInterface $strand, Exception $exception)
{
$throwException = true;
$preventDefault = function () use(&$throwException) {
$throwException = false;
};
$strand->emit('error', [$strand, $exception, $preventDefault]);
$strand->emit('exit', [$strand]);
$strand->removeAllListeners();
$strand->pop();
$strand->suspend();
if ($throwException) {
throw $exception;
}
}
/**
* Start the coroutine.
*
* @param StrandInterface $strand The strand that is executing the coroutine.
*/
public function call(StrandInterface $strand)
{
$method = [$strand->kernel()->api(), $this->name];
if (!is_callable($method)) {
$strand->throwException(new BadMethodCallException('The kernel API does not have an operation named "' . $this->name . '".'));
return;
}
$strand->pop();
$arguments = $this->arguments;
array_unshift($arguments, $strand);
// If the kernel API implementation returns a non-null value it is
// treated as a coroutine to be executed. This allows implementation of
// kernel API operations to be implemented as generators.
$coroutine = call_user_func_array($method, $arguments);
if (null !== $coroutine) {
$strand->call($coroutine);
}
}
