public static IOptionEnumerable <TResult> SelectMany <TSuccess, TBind, TResult>(this IOptionEnumerable <TSuccess> source, Func <TSuccess, 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
.Select(result => result
.Match(success =>
bind
.Invoke(success)
.Map(value => resultSelector.Invoke(success, value)),
Option.None <TResult>
)
)
.AsOptionEnumerable());
}
public static IOptionEnumerable <TValue> Where <TValue>(this IOptionEnumerable <TValue> source, Func <TValue, Option <Unit> > failurePredicate)
=> source
.Select((Func <Option <TValue>, Option <TValue> >)(value => value
.Bind((Func <TValue, Option <TValue> >)(success => (Option <TValue>)OptionExtensions.Map <Unit, TValue>(failurePredicate
.Invoke((TValue)success)
, (Func <Unit, TValue>)(_ => (TValue)success)))
))
)
.AsOptionEnumerable();
public static IOptionEnumerable <TValue> Where <TValue>(this IOptionEnumerable <TValue> source, Func <TValue, Option <Unit> > failurePredicate)
=> source
.Select(value => value
.Bind(success => failurePredicate
.Invoke(success)
.Select(_ => success)
)
)
.AsOptionEnumerable();
public static IOptionEnumerable <TResult> Select <TSuccess, TResult>(this IOptionEnumerable <TSuccess> source, Func <TSuccess, TResult> selector)
{
if (selector == null)
{
throw new ArgumentNullException(nameof(selector));
}
return(source
.Select(result => result
.Match(
success => Option.Some(selector.Invoke(success)),
Option.None <TResult>
)
)
.AsOptionEnumerable());
}