The document discusses asynchronous programming using generators and fibers. It shows how to define generators that yield values, consume and produce items in a queue asynchronously, and execute asynchronous tasks using the await keyword. Fibers are lightweight threads that can suspend execution and are scheduled concurrently using a scheduler. Exceptions must be caught and propagated properly when using fibers.

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14. function* calculatingGenerator(start, dest) {
let value = 0
for (let i = start; i < dest; i++) {
if (i == 2) value *= 10
else value += 1
yield value
}
}
const iterator = calculatingGenerator(0, 3)
console.log(iterator.next()) // { done: false, value: 1 }
console.log(iterator.next()) // { done: false, value: 2 }
console.log(iterator.next()) // { done: false, value: 20 }
console.log(iterator.next()) // { done: true, value: undefined }
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var q := new queue
generator produce
loop
while q is not full
create some new items
add the items to q
yield consume
generator consume
loop
while q is not empty
remove some items from q
use the items
yield produce
subroutine dispatcher
var d := new dictionary(generator → iterator)
d[produce] := start produce
d[consume] := start consume
var current := produce
loop
current := next d[current]

16. async Task<Toast> MakeToastWithButterAndJamAsync(int number)
{
var toast = await ToastBreadAsync(number);
ApplyButter(toast);
ApplyJam(toast);
return toast;
}
async function f() {
let promise = new Promise((resolve, reject) => {
setTimeout(() => resolve("done!"), 1000)
});
let result = await promise; // wait till the promise resolves (*)
alert(result); // "done!"
}

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Class a{
void method1(){
method2();
…
}
void method2(){
…
}
}

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22. public final void pushMethod(int entry, int numSlots) {
pushed = true;
int idx = sp - FRAME_RECORD_SIZE;
long record = dataLong[idx];
record = setEntry(record, entry);
record = setNumSlots(record, numSlots);
dataLong[idx] = record;
int nextMethodIdx = sp + numSlots;
int nextMethodSP = nextMethodIdx + FRAME_RECORD_SIZE;
if (nextMethodSP > dataObject.length)
growStack(nextMethodSP);
// clear next method's frame record
dataLong[nextMethodIdx] = 0L;
}

23. public final void popMethod(int slots) {
pushed = false;
final int oldSP = sp;
final int idx = oldSP - FRAME_RECORD_SIZE;
final long record = dataLong[idx];
final int newSP = idx - getPrevNumSlots(record);
// clear frame record (probably unnecessary)
dataLong[idx] = 0L;
// help GC
for (int i = oldSP; i < oldSP + slots && i < dataObject.length; i++)
dataObject[i] = null;
sp = newSP;
}

24. private transient FiberScheduler scheduler =
new FiberForkJoinScheduler("test", parallelism:1, monitorType:null, detaildInfo:false);
Fiber fiber = new Fiber(scheduler, new SuspendableRunnable() {
@Override
public void run() throws SuspendExecution {
try {
System.out.print("Fiber run");
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}).start();
fiber.join();

25. final Fiber<Integer> fiber1 = new Fiber<Integer>(scheduler, new SuspendableCallable<Integer>() {
@Override
public Integer run() throws SuspendExecution {
Fiber.park(100, TimeUnit.MILLISECONDS);
return 123;
}
}).start();
final Fiber<Integer> fiber2 = new Fiber<Integer>(scheduler, new SuspendableCallable<Integer>() {
@Override
public Integer run() throws SuspendExecution, InterruptedException {
try {
int res = fiber1.get();
return res;
} catch (ExecutionException e) {
throw Exceptions.rethrow(e.getCause());
}
}
}).start();
int res = fiber2.get();
assertThat(res, is(123));
assertThat(fiber1.get(), is(123));

26. function () throws SuspendExecution {
nested();
}
void nested() throws SuspendExecution {
Fiber.park();
}
function () {
nested();
}
void nested() throws SuspendExecution {
Fiber.park(); // occur error!!!
}

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32. @Override
public final boolean onLogin(...) throws SuspendExecution {
// load data from db.
UserEntity userEntity = AsyncAwait.call(RpsConfig.DB_THREAD_POOL,new Callable<UserEntity>() {
@Override
public UserEntity call() throws Exception {
return PersistenceManager.getInstance().findByKey(UserEntity.class, reqMsg.getUserId());
}
});
int money = userEntity.getMoney();
// http request
FiberHttpRequest fiberHttpRequest = new FiberHttpRequest(httpRequestTestURL);
HttpResponse httpResponse = fiberHttpRequest.GET();
TestOption httpRequestOption = httpResponse.getContents(TestOption.class);
int getMaxConnTotal = httpRequestOption.getMaxConnTotal();
.
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