Just a quick post as I've not had a lot of time to play with Haskell just recently. This morning I noticed Jonathan Lang's post to perl6-language asking if the ternary operator ?? !! could be turned into two binary operators. I thought this had been discussed some time back, but apparently not. Audrey commented […]

I start off confidently, typing in the first example into my scratch file: > data Tree = Leaf a | Branch (Tree a) (Tree a) Of course, ghci complains bitterly, and strangely Prelude> :l 7.hs [1 of 1] Compiling Tree ( 7.hs, interpreted ) 7.hs:5:19: Not in scope: type variable `a' 7.hs:5:36: Not in scope: […]