trait ErrorDetector
{
public function onError(Promisable $promised)
{
printf("Oh noes: %s\n", (string) $promised->getError());
}
}
class AddTwo extends Thenable
{
use ErrorDetector;
public function onFulfilled(Promisable $promised)
{
$promised->meaning += 2;
/* throwing an exception here will cause invocation of
PrintMeaning::onError */
}
}
class PrintMeaning extends Thenable
{
use ErrorDetector;
public function onFulfilled(Promisable $promised)
{
printf("The meaning of life + 2: %d\n", $promised->meaning);
/* You can access exceptions thrown here using $promised->getError */
}
}
$manager = new PromiseManager();
$promise = new Promise($manager, new CalculateTheMeaningOfLife());
$promise->then(new AddTwo($promise))->then(new PrintMeaning($promise));
$manager->shutdown();
}
throw new \RuntimeException("failed to load HTML at {$promised->url}");
}
}
}
class DOMPrinter extends Thenable
{
use DOMError;
public function onFulfilled(Promisable $promised)
{
$promised->getLogger()->log("%s: %s\n", $promised->getName(), $promised->getDescription());
/* allow the object to be collected */
$promised->setGarbage(true);
}
}
/* start a pool of 8 threads to fulfill promises */
$manager = new PromiseManager(8);
/* get 100 random internal function names */
$functions = get_defined_functions();
foreach (array_rand($functions["internal"], 100) as $function) {
$names[] = $functions["internal"][$function];
}
$functions = $names;
/* create a logger for threads in the pool to share */
$logger = new SafeLogger();
/* create promises */
foreach ($functions as $index => $function) {
$functions[$index] = new Promise($manager, new DOMFetcher($logger, $function));
$functions[$index]->then(new DOMParser($functions[$index]))->then(new DOMPrinter($functions[$index]));
}
/* begin to collect ... */
while ($manager->hasWork()) {