public static IAsyncOptionEnumerable <TResult> SelectMany <TSuccess, TBind, TResult>(this IAsyncOptionEnumerable <TSuccess> source, Func <TSuccess, Task <Option <TBind> > > bind, Func <TSuccess, TBind, TResult> resultSelector)
where TSuccess : 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)
.Map(value => resultSelector.Invoke(success, value)),
() => Task.FromResult(Option.None <TResult>())
)
)
.AsAsyncOptionEnumerable());
}
public static IAsyncOptionEnumerable <TValue> Where <TValue>(this IAsyncOptionEnumerable <TValue> source, Func <TValue, Task <Option <Unit> > > failurePredicate)
=> source
.SelectAsync(value => value
.BindAsync(success => failurePredicate
.Invoke(success)
.Map(_ => success)
)
)
.AsAsyncOptionEnumerable();
public static IAsyncOptionEnumerable <TResult> Select <TSuccess, TResult>(this IAsyncOptionEnumerable <TSuccess> source, Func <TSuccess, Task <TResult> > selector)
{
if (selector == null)
{
throw new ArgumentNullException(nameof(selector));
}
return(source
.SelectAsync(result => result
.MatchAsync(
success => Option.SomeAsync(selector.Invoke(success)),
() => Task.FromResult(Option.None <TResult>())
)
)
.AsAsyncOptionEnumerable());
}