[Haskell-cafe] Re: Stronger STM primitives needed? Or am I just doing it wrong?

[Wouter Swierstra]

On 24 Apr 2008, at 12:02, apfelmus wrote:

> Sounds good. But I wonder what "obscure" optimization comes next;  
> can we have a toy-model of STM? I mean, it should be possible to  
> express both the "continuation-logging" and "read-only-fail"  
> optimization in terms of
>
>  type STM a = Maybe a
>
> or similar?

There's a pure version of STM in the latest version of the IOSpec  
library:

http://hackage.haskell.org/cgi-bin/hackage-scripts/package/IOSpec-0.2

I've used it to test a few non-trivial applications. I should warn you  
that it does use a very simple stop-the-world semantics - the model  
may not be fine-grained enough to try out all kinds of optimisations.

   Wouter