def head

def take (int n) ([] xs)

def map (Func func) ([] xs)

def max ([] xs)

def min ([] xs)

def sum ([] xs)

def product ([] xs)

def rev ([] xs)

def foldr (Func func) u (x:xs)

def foldr1 (Func func) (x:y:xs)

def foldl (Func func) u (x:xs)

def elem x (y:ys)

def takewhile (Func func) ([] xs)

def dropwhile (Func func) (x:xs)

def filter (Func func) ([] xs)

def zipwith (Func func) ([] xs) ([] ys)

def zip ([] xs) ([] ys)

def iterate2 func first second

def iterate3 func first second third

def range(start, end,  step) | def range (first, second) (end) | def range (start) (end)

def concatenation ([] left) ([] right) | def concatenation(string str1)(string str2)