DDC compiler and effects; better than Haskell? (was Re: [Haskell-cafe] unsafeDestructiveAssign?)

[John A. De Goes]

So what, because effect systems might not eliminate *all* boilerplate,  
you'd rather use boilerplate 100% of the time? :-)

Regards,

John A. De Goes
N-Brain, Inc.
The Evolution of Collaboration

http://www.n-brain.net    |    877-376-2724 x 101

On Aug 12, 2009, at 3:28 PM, Dan Doel wrote:

> On Wednesday 12 August 2009 10:12:14 am John A. De Goes wrote:
>> I think the point is that a functional language with a built-
>> in effect system that captures the nature of effects is pretty damn
>> cool and eliminates a lot of boilerplate.
>
> It's definitely an interesting direction (possibly even the right  
> one in the
> long run), but it's not without its faults currently (unless things  
> have
> changed since I looked at it).
>
> For instance: what effects does disciple support? Mutation and IO?  
> What if I
> want non-determinism, or continuations, etc.? How do I as a user add  
> those
> effects to the effect system, and specify how they should interact  
> with the
> other effects? As far as I know, there aren't yet any provisions for  
> this, so
> presumably you'll end up with effect system for effects supported by  
> the
> compiler, and monads for effects you're writing yourself.
>
> By contrast, monad transformers (for one) let you do the above  
> defining of new
> effects, and specifying how they interact (although they're  
> certainly neither
> perfect, nor completely satisfying theoretically).
>
> Someone will probably eventually create (or already has, and I don't  
> know
> about it) an extensible effect system that would put this objection  
> to rest.
> Until then, you're dealing in trade offs.
>
> -- Dan