Re: Proposal: Move primitive-Data.Primitive.Addr API into base

The point , hahah, of a Ptr void is that you can’t dereference it. But you certainly can cast it and do address arithmetic on it!! On Mon, Oct 29, 2018 at 10:10 AM David Feuer wrote:

On Mon, Oct 29, 2018, 10:05 AM Sven Panne wrote:

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Am Mo., 29. Okt. 2018 um 14:27 Uhr schrieb Daniel Cartwright < chessai1996@gmail.com>:

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'Ptr Void' is not a pointer to a value of type 'Void'; there are no values of type 'Void': this type is nonsensical.

That's the whole point, and it actually makes sense: If you see "Ptr Void", you can't do much with it, apart from passing it around or using castPtr on it. This is exactly what should be achieved by using "Ptr Void" in an API. This is basically the same as "void *" in C/C++.

No, it does not make sense. The approximate equivalent of C's void* is Ptr Any. Ptr Void promises to give you anything you want on dereference, which is nonsense.

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You can't store or read "()", so the same holds as for Void (which didn't exist when the FFI was created IIRC).

Sure you can. Storing () does nothing and reading it gives (). Our () is somewhat similar to C's void return type. _______________________________________________ Libraries mailing list Libraries@haskell.org http://mail.haskell.org/cgi-bin/mailman/listinfo/libraries