demo.pk

def reduce(func: (Int, Int => Int), acc: Int, l: List[Int]): Int =>
  if(is_empty(l)):
    acc
  else:
    reduce(func, func(hd(l), acc), tl(l))

def map(f: (Int => Int), l: List[Int]): List[Int] =>
  if(is_empty(l)):
    l
  else:
    f(hd(l))::(map(f, tl(l)))

def even(n: Int): Bool =>
  if(n % 2 is 0):
    True
  else:
    False

val x = [1,2,3,4] |> map((x:Int => x + 5 :Int)) |> reduce((x: Int, y: Int => x + y : Int), 0) |> even 

print("Example 1: Functional Programming Styles [see source]")
print(x)

print("\nExample 2: Functional Composition [see source]")
def gcd(a : Int, b : Int) : Int =>
  if(b is 0):
    a
  else:
    gcd(b, a % b)

def relativePrimes(a: Int) =>
  if (a is 1):
    True
  else:
    False

val p = relativePrimes <<  gcd

if(p(25, 15)):
  print("You have relative primes")
else:
  print("Not relative primes")