18 Aug
2020
18 Aug
'20
5:18 p.m.
That’s a really nice idea ! On Tue, Aug 18, 2020 at 2:54 AM Henning Thielemann < lemming@henning-thielemann.de> wrote:
On Mon, 17 Aug 2020, Carter Schonwald wrote:
There’s an interesting idea or two in here. Like, should we support
having non-nullable pointers?
That was my first idea, too.
newtype NonNullPtr a = NonNullPtr (Ptr a)
maybeNonNull :: Ptr a -> Maybe (NonNullPtr a)
Using NonNullPtr in FFI declarations would make the interfaces safer.
E.g.
dst <- mallocArray n
for (maybeNonNull dst) $ \dstNonNull ->
copyArray dstNonNull srcNonNull n
That seems better than testing for nullPtr and then forgeting this
information in the type, again.