| > > In the list of features "required for Haskell in practice", bang patterns are | > > way up there. | > | > But their syntax has issues: | > | > a!b = ... | > | > Did I just define the function "a" or the function "!"? | | Interesting note, if we solve this, then we can apply the same thing to | the treatment of ~ and regain it as a usable operator. In GHC I implemented a pretty grotesque hack. I really really wanted f !x !y = e to work as you'd expect. But because of the infix operator thing, that parses as (f ! x) ! y = e A gruesome post-processing step restores the parse we want, for the special case of !. It's not nice, but I didn't have the luxury of changing anything else, which we do now. Not allowing infix functions on the LHS would be a notable simplification. Constructors in patterns should still be infix of course: f (a :=: b) = ... In any case, I've always thought this was weird: Just x == Just y = x == y Simon