Simon Marlow wrote:
Ian Lynagh wrote:
Simon Marlow wrote:
But there's a solution: we could remove the "standard" modules from base, and have them only provided by haskell-std (since base will just be a re-exporting layer on top of base-internals, this will be easy to do). Most packages will then have dependencies that look like
build-depends: base-4.*, haskell-std-2010
We'll probably end up with situations where one dependency of a package needs haskell-std-2010, and another needs haskell-std-2011. I don't know which impls support that at the moment.
That's the case with base-3/base-4 at the moment. Is it a problem?
I think the issue raised is the diamond import problem, for instance that say the list type from haskell-std-2010 is spuriously different from the one in haskell-std-2011 . This would affect new programs based on the 2011 standard that want to use older libraries based on the 2010 standard; the point being that the latter are "intentionally" not updated to the newer standard. Of course, that's just the base-3 / base-4 issue which can be solved; it's just that it's not automatic but needs explicit work by implementors every time there is a new library standard. Regards, apfelmus -- http://apfelmus.nfshost.com