Question: Why does IEnumerable<T>.ToOption resolves to Option<T>?

[LaszloLueck]

Hello,
why does IEnumerable<T>.ToOption transform to Option<T> and not to Option<IEnumerable<T>>?
And, if the IEnumerable<T> is not null, the Head (first entry) gives back as result?

I wrote myself a helper method that implement it more type-in, type-out.

[Pure]
public static Option<IEnumerable<T>> ToOption<T>(this IEnumerable<T>? self) => self.IsNull() ? Option<IEnumerable<T>>.None : self.ToSome();

From here, you can just resolve the option with IfNone....
e.g.

IEnumerable<string>? nullList = null;
var res = nullList.ToOption().IfNone(Array.Empty<string>());

And res is
a) an empty IEnumerable (if null) or the filled one.
b) the incoming IEnumerable as Value if it is not null

Thanks and Regards,
Laszlo

[louthy]

ToOption(), like all of the To* methods, is a natural-transformation, not a lifting operation. You can think of them as conversion functions. Lifting is usually done by the constructor functions, like Some(x), Right(x), FinSucc(x) etc.

In this case, the exact functionality you're looking for is in Optional(xs)

[LaszloLueck]

You´re absolutely right!
I made a small mistake, when i searching around for the right implementation.
I forgot to import
using static LanguageExt.Prelude;
So with that import works Optional(nullable) like a charm.

I think it is time to set
global using static LanguageExt.Prelude;
in the main.

Thanks a lot,

Laszlo