22:49 <endformationage> Here's an FFI related question:

22:50 <endformationage> I have a C function which takes a `void* data`, where data is really an array on U8 or floats.

22:52 <endformationage> Passing a Pony Array[U8] is easily done, by calling the array's `cpointer()`, and assigning the type `Pointer[U8] tag` to the FFI functions parameter.

22:53 <endformationage> Of course, calling `cpointer()` on an Array[F32] results in a `Pointer[F32] tag`, which will not be acceptable to the use declaration of the FFI function.

22:55 <Praetonus> endformationage: You can use a `Pointer[None]`. It's a generic pointer similar to void* when used as an FFI parameter type

22:55 <endformationage> The C side of things is able to determine whether data should be interpreted as unsigned char or float, via other params to the function.

22:55 <endformationage> Ah, awesome. Thanks Praetonus!

23:26 <endformationage> If I want to have ageneric type parameter that accepts only 2 types, to I just define it as a union type? i.e. [T: (Foo | Bar)]

23:32 <endformationage> Hmm, am I correct to say constructors cannot be generic with the class being so?

23:33 <endformationage> As in, it doesn't make sense to make a constructor a generic method.

23:43 <Praetonus> endformationage: Yes to the union type as a type parameter constraint

23:43 <endformationage> * I meant to ask: Am I correct to say constructors cannot be generic WITHOUT the class being so?

23:44 <endformationage> I've made a constructor in the form of a generic method, and I'm attempting to assign a generically typed datum to a field of the class, which is not generically typed (though is typed the same as the constraints would allow).

23:44 <endformationage> I think I need to make the class generic.

23:44 <Praetonus> endformationage: Constructors can be generic even when the associated type isn't. Do you have some code to illustrate your problem?

23:51 <endformationage> Praetonus: Here's a gist: https://gist.github.com/patternspandemic/4d759050ed4efa294e78a85bccf80f58

23:53 <endformationage> Perhaps the issue is with my dealing with the union type field and param

23:58 <Praetonus> endformationage: So the issue here is that an `(X | Y)` constraint also accepts the `(X | Y)` type itself. Which means that the type argument could be `Array[(U8 | F32)]`, and the type checker is catching that

23:59 <Praetonus> You need to specify that your type parameter can only be a concrete type, but I'm not sure how to do that

23:59 <endformationage> Ah, hmm, OK.

23:59 <Praetonus> You could try posting a message on the mailing list, maybe somebody has a solution