(I accidentally posted this to ffi@haskell.org yesterday...) Glynn Clements wrote:

Wolfgang Thaller wrote:

...

2) CGA implementations should automatically do all necessary synchronization so that the CGA fully supports concurrency even if the backend library does not.

I suspect that this might be a bad idea, and I'm not totally sure that it's even possible. I think that it would be better to defer this decision until the feasibility can be assessed.

While different implementations might in some cases be slightly more complex than just using locks, I don't see why it should be impossible. After all, thread-safe toolkits are not new. Do you have any specific problems in mind? Also, it should be noted that this feature is important: Unless we have this or an equivalent, it will _not_ be possible to use concurrent Haskell for writing GUI programs. Of course, we could still agree that it is a goal, add something like "unless it turns out to be infeasible" and then revisit the issue later. Cheers, Wolfgang