private static async Task <T> GetOrAddAsync <T>(
ObjectCache cache, string key, CacheItemPolicy policy, Func <Task <T> > valueFactory)
{
var newEntry = new LazyTask <T>(valueFactory);
if (cache.AddOrGetExisting(key, newEntry, policy) is LazyTask <T> existingEntry)
{
return(await existingEntry.Value);
}
try
{
Task <T> result = newEntry.Value;
if (result.IsCanceled || result.IsFaulted)
{
cache.Remove(key);
}
return(await result);
}
catch
{
cache.Remove(key);
throw;
}
}
public async Task <bool> Validate()
{
return(await Conditions.AllFalseAsync(
LazyTask <bool> .Create(() => Task.FromResult(false)).Get(),
LazyTask <bool> .Create(async() => await ValidateSomenthing()).Get(),
LazyTask <bool> .Create(async() => await ValidateAnoterThing()).Get()
));
}
IEnumerator Work()
{
var t1 = Observable.Interval(TimeSpan.FromSeconds(1)).Take(4).ToLazyTask();
var t2 = Observable.Interval(TimeSpan.FromSeconds(1)).Select(x => x * x).Take(4).ToLazyTask();
var t3 = Observable.Throw <Unit>(new Exception()).ToLazyTask();
yield return(LazyTask.WhenAll(t1, t2, t3));
logger.Debug(t1.Result + ":" + t2.Result);
logger.Debug(t3.Exception);
}
