public static IEnumerable <TResult> ZipAny <T1, T2, TResult>(
this IEnumerable <T1> first,
IEnumerable <T2> second,
Func <T1, T2, Maybe <TResult> > resultSelector)
{
#if true || PLAIN_LINQ
return(Maybe.CollectAny(first.Zip(second, resultSelector)));
#else
return(from x in first.Zip(second, resultSelector)
where x.IsSome
select x.Value);
#endif
}
public static IEnumerable <TResult> SelectAny <TSource, TResult>(
this IEnumerable <TSource> source,
Func <TSource, Maybe <TResult> > selector)
{
#if PLAIN_LINQ
return(Maybe.CollectAny(source.Select(selector)));
#else
if (selector is null)
{
throw new Anexn(nameof(selector));
}
return(from x in source
let m = selector(x)
where m.IsSome
select m.Value);
#endif
}
