GitHub - Cysharp/ValueTaskSupplement: Append supplemental methods(WhenAny, WhenAll, Lazy) to ValueTask. (original) (raw)
ValueTaskSupplement
ValueTask<T> is a new standard of define async methods especially after being introduced IValueTaskSource. But it lacks utility like WhenAny, etc. ValueTaskSupplement appends supplemental methods(WhenAny, WhenAll, Lazy) to ValueTask and it is implemented by IValueTaskSource so fast and less allocation.
PM> Install-Package ValueTaskSupplement
Table of Contents
How to Use
using ValueTaskSupplement; // namespace
async ValueTask Demo()
{
// ValueTaskEx is the only types from provided this library
// like this individual types
ValueTask<int> task1 = LoadAsyncA();
ValueTask<string> task2 = LoadAsyncB();
ValueTask<bool> task3 = LoadAsyncC();
// await ValueTasks(has different type each other) with tuple
var (a, b, c) = await ValueTaskEx.WhenAll(task1, task2, task3);
// WhenAny with int winIndex
var (winIndex, a, b, c) = await ValueTaskEx.WhenAny(task1, task2, task2);
// like Timeout
var (hasLeftResult, value) = await ValueTaskEx.WhenAny(task1, Task.Delay(TimeSpan.FromSeconds(1)));
if (!hasLeftResult) throw new TimeoutException();
// Lazy(called factory once and delayed)
AsyncLazy<int> asyncLazy = ValueTaskEx.Lazy(async () => 9999);}
WhenAll
// Same type and return array(same as Task.WhenAll). public static ValueTask<T[]> WhenAll(IEnumerable<ValueTask> tasks);
// T0, T1, to... public static ValueTask<(T0, T1)> WhenAll<T0, T1>(ValueTask task0, ValueTask task1); ... // T0 ~ T15 public static ValueTask<(T0, T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12, T13, T14, T15)> WhenAll<T0, T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12, T13, T14, T15>(ValueTask task0, ValueTask task1, ValueTask task2, ValueTask task3, ValueTask task4, ValueTask task5, ValueTask task6, ValueTask task7, ValueTask task8, ValueTask task9, ValueTask task10, ValueTask task11, ValueTask task12, ValueTask task13, ValueTask task14, ValueTask task15);
IEnumerable<ValueTask<T>> and (ValueTask<T0>, ValueTask<T1>, ...) can await directly.
using ValueTaskSupplement;
// same as ValueTaskEx.WhenAll(new []{ }), ValueTaskEx.WhenAll(A, B, C) var result = await new[] { LoadAsyncA(), LoadAsyncB(), LoadAsyncC() }; var (x, y, z) = await (LoadAsyncA(), LoadAsyncB(), LoadAsyncC());
WhenAny
// binary api is useful to await with Delay(like for check Timeout). public static ValueTask<(bool hasResultLeft, T result)> WhenAny(ValueTask left, Task right); public static ValueTask<(bool hasResultLeft, T result)> WhenAny(ValueTask left, ValueTask right);
// receive sequence is like Task.WhenAny but returns int winArgumentIndex.
public static ValueTask<(int winArgumentIndex, T result)> WhenAny(IEnumerable<ValueTask> tasks);
// Return result of tuple methods is guaranteed only winArgumentIndex value public static ValueTask<(int winArgumentIndex, T0 result0, T1 result1)> WhenAny<T0, T1>(ValueTask task0, ValueTask task1); ... // T0 ~ T15 public static ValueTask<(int winArgumentIndex, T0 result0, T1 result1, T2 result2, T3 result3, T4 result4, T5 result5, T6 result6, T7 result7, T8 result8, T9 result9, T10 result10, T11 result11, T12 result12, T13 result13, T14 result14, T15 result15)> WhenAny<T0, T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12, T13, T14, T15>(ValueTask task0, ValueTask task1, ValueTask task2, ValueTask task3, ValueTask task4, ValueTask task5, ValueTask task6, ValueTask task7, ValueTask task8, ValueTask task9, ValueTask task10, ValueTask task11, ValueTask task12, ValueTask task13, ValueTask task14, ValueTask task15);
Lazy
// AsyncLazy is similar to Lazy, it can store in field // it await directly or can convert to ValueTask easily to use WhenAll. public static AsyncLazy Lazy(Func<ValueTask> factory);
public class AsyncLazy
{
public ValueTask AsValueTask();
public ValueTaskAwaiter GetAwaiter();
public static implicit operator ValueTask(AsyncLazy source);
}
Factory
public static ValueTask FromResult(T result); public static ValueTask FromTask(Task result); public static ValueTask FromTask(Task result); public static ValueTask AsValueTask(this Task result); public static ValueTask AsValueTask(this Task result);
License
This library is under the MIT License.