On 2008-04-23, Simon Marlow
Johan Tibell wrote:
An interesting question. What is the goal of Haskell'? Is it to, like Python 3000, fix warts in the language in an (somewhat) incompatible way or is it to just standardize current practice? I think we need both, I just don't know which of the two Haskell' is.
The stated goal is still for Haskell' to be a language that is stable and relevant for large-scale development for several years to come.
It is mainly a consolidation effort: that is, we aim to standardise existing practice in the form of language extensions that are currently implemented and widely used. Having said that, the standardisation process gives us the opportunity to critically assess the design of these extensions, and the design of the system as a whole, and as a result we may wish to make changes in order that the resulting language does not have inconsistencies, design flaws, or critical omissions.
Given a fairly limited goal of "consolidating current practice", not much should change. And this is a very useful thing to do. The problem is that many of us don't see any opportunity for large change after this. We expect any changes in the hypothetical Haskell 2 (or 201x) to be resisted tooth and nail by the larger crowd as Haskell grows. And there is a lot that clearly isn't battle tested in a reasonable new form, though the current practice is widely agreed upon to be broken. Examples include all monads having fail, rather than only those in a subclass, monad not being a subclass of functor, and the whole numeric hierarchy issue (which I don't think can be properly designed unless we know whether it's going to be FDs or ATs, though, of course, designing it for either would provide valuable experience for the limitations of both), Many of these are "mere" library changes, but library changes that are nearly as fundamental as language changes, because of how tied in the prelude is currently. It's still not entirely straightforward to replace the prelude with a custom one, which makes it harder to test some of these changes in real world use. All of these factors combine to make the ones who get annoyed with these problems to want to shoehorn in changes right now. -- Aaron Denney -><-