andrewcoppin:
Jonathan Cast wrote:
On Thursday 05 July 2007, Andrew Coppin wrote:
...OK, anybody have a solution that works in Haskell 98?
Rank-2 types are perhaps /the/ most common, widely accepted extension to Haskell 98, after the approved addendum for FFI and the draft addendum for hierarchical modules. I would really be concerned about using them (it's certainly not like they're going to just disappear on you one day, like say functional dependencies almost certainly will). But that's just me.
Personally, I just try to avoid *all* language extensions - mainly because most of them are utterly incomprehensible. (But then, perhaps that's just because they all cover extremely rare edge cases?)
Some cover edge cases, some are just useful. What about: * the FFI * bang patterns * pattern guards * newtype deriving Surely, fairly simple, useful. Used a lot? :-) -- Don