====== Let and where constructs ====== ===== Hard differences ===== ==== Inside expression ==== * let constructs are legal * example code:


main = print (1 + (let i = 10 in 2 * i + 1))

* where constructs are ilegal * example code:


main = print (1 + (2 * i + 1 where i = 10))

==== Function that use functions ==== * where constructs are legal * example code:


hasVowel [] = False
hasVowel (x:xs)
  | x `elem` vowels = True
  | otherwise = False
  where vowels = "AEIOUaeiou"

* let constructs are ilegal * example code:


let vowels = "AEIOUaeiou"
in hasVowel = ...

===== ✎ ===== ~~DISCUSSION~~