Re: Proposal: EPHEMERAL pragma

On 25.10.2012, at 16:45, Johan Tibell wrote:

Interesting idea.

On Thu, Oct 25, 2012 at 6:56 AM, José Pedro Magalhães wrote:

...

3. Emit a warning if the generated core code still contains uses of Rep.

I think this part will be really annoying, as GHC might end up generating warnings that the programmer can do nothing about (because some optimization failed to remove Rep).

I think this is exactly the right idea. A compiler should emit errors about bad typing since type inference is somewhat complete, but should emit warnings about other incomplete analyses or optimizations. If you think that this is too noisy, by all means, don't emit these warnings by default and add a flag that enables them. my 2p, Axel