Stephanie,
What do you mean by "local redefinitions"?
I suppose it could be described as "scoped specializability"; see Chapter 8 of Andres' thesis [1]. Examples of local redefinitions in GH: -- case-insenstive equality let equals {| a |} c1 c2 = equals {| Char |} (toUpper c1) (toUpper c2) in equals {| [a] |} "Hello" "hEllo" -- length of the list let size {| a |} x = 1 in size {| [a] |} [2, 3, 5, 7] -- map toUpper let map {| a |} = toUpper in map {| [a] |} "Hello, world!" -- flattens the list of lists let collect {| a |} x = [x] in collect {| [[a]] |} xss -- unlines let collect {| a |} s = s ++ "\n" in collect {| [a] |} ["Hello", "World"] Cheers, Stefan ---- [1] Andres Loeh. Exploring Generic Haskell. Ph.D. thesis, Utrecht University, 2004.