Surprisingly, not really. {-# OPTIONS -fglasgow-exts #-} class BuildList a r | r-> a where build' :: [a] -> a -> r instance BuildL

Surprisingly, not really. {-# OPTIONS -fglasgow-exts #-} class BuildList a r | r-> a where build' :: [a] -> a -> r instance BuildList a [a] where build' l x = reverse$ x:l instance BuildList a r => BuildList a (a->r) where build' l x y = build'(x:l) y varargs x = build' [] x main = print $ ( sum $ varargs 1 2 3 4 5 6 100) $ ./Test 121 http://okmij.org/ftp/Haskell/vararg-fn.lhs http://okmij.org/ftp/Haskell/vararg-fn.lhs