You also need to avoid inspecting the StablePtr itself, which is just a
number, to maintain purity. The whole thing is a bit weird. Why do you want
this anyway?
On Wed, Aug 21, 2019, 7:39 AM David Feuer wrote:
> So something like
>
> newtype StablePtr a = StablePtr (StablePtrST RealWorld a)?
>
So something like
newtype StablePtr a = StablePtr (StablePtrST RealWorld a)?
I suppose that could work with some discipline. You have to assume that
foreign code doesn't pick its address out of a hat and so something silly,
but I guess you pretty much have to assume that anyway.
On Wed, Aug 21,
I have been doing some work where i want `StablePtr`, but also to not
be confined to `IO`. I saw the following comment in
"compiler/prelude/PrimOp.hs":
Question: Why @RealWorld@ - won't any instance of @_ST@ do the job? [ADR]
It has been there for 20 years. What is the answer? If it is safe i'll
