public static IAsyncResultEnumerable <TResult, TFailure> SelectMany <TSuccess, TFailure, TBind, TResult>(this IAsyncResultEnumerable <TSuccess, TFailure> source, Func <TSuccess, Task <Result <TBind, TFailure> > > bind, Func <TSuccess, TBind, Task <TResult> > resultSelector)
where TSuccess : notnull
where TFailure : notnull
where TBind : notnull
where TResult : notnull
{
if (bind == null)
{
throw new ArgumentNullException(nameof(bind));
}
if (resultSelector == null)
{
throw new ArgumentNullException(nameof(resultSelector));
}
return(source
.SelectAsync(result => result
.MatchAsync(success =>
bind
.Invoke(success)
.MapAsync(value => resultSelector.Invoke(success, value)),
failure => Task.FromResult(Result.Failure <TResult, TFailure>(failure))
)
)
.AsAsyncResultEnumerable());
}
public static IAsyncResultEnumerable <TSuccess, TFailure> Where <TSuccess, TFailure>(this IAsyncResultEnumerable <TSuccess, TFailure> source, Func <TSuccess, Task <Result <Unit, TFailure> > > failurePredicate)
=> source
.SelectAsync(value => value
.BindAsync(success => failurePredicate
.Invoke(success)
.Select(_ => success)
)
)
.AsAsyncResultEnumerable();
public static IAsyncResultEnumerable<TResult, TFailure> Select<TSuccess, TResult, TFailure>(this IAsyncResultEnumerable<TSuccess, TFailure> source, Func<TSuccess, Task<TResult>> selector)
{
if (selector == null)
throw new ArgumentNullException(nameof(selector));
return source
.SelectAsync(result => result
.MatchAsync(
success => Result.Success<TResult, TFailure>(selector.Invoke(success)),
failure => Task.FromResult(Result.Failure<TResult, TFailure>(failure))
)
)
.AsAsyncResultEnumerable();
}
