I build software that
builds itself.

main =
  let _ = print "Hello from Rail!"
  let _ = print "Running as WebAssembly."
  0

fib n =
  if n < 2 then n
  else fib (n - 1) + fib (n - 2)

main =
  let _ = print (fib 10)
  let _ = print (fib 20)
  let _ = print (fib 30)
  0

square x = x * x
cube x = x * x * x

main =
  let _ = print (square 7)
  let _ = print (cube 5)
  let _ = print (square 12 + cube 3)
  0

main =
  let xs = [10, 20, 30, 40]
  let _ = print (show (head xs))
  let _ = print (show (length xs))
  let _ = print (show (head (tail (tail xs))))
  0

type Shape =
  | Circle r
  | Rect w h

area s = match s
  | Circle r -> r * r * 3
  | Rect w h -> w * h

main =
  let _ = print (show (area (Circle 5)))
  let _ = print (show (area (Rect 4 7)))
  let _ = print (show (area (Circle 10)))
  0

apply f x = f x

main =
  let scale = 10
  let mul = \x -> x * scale
  let _ = print (show (apply mul 7))
  let offset = 100
  let add = \x -> x + offset
  let _ = print (show (apply add 42))
  0

fizzbuzz n = if n > 20 then 0
  else
    let _ = if (n % 15) == 0
      then print "FizzBuzz"
      else if (n % 3) == 0
      then print "Fizz"
      else if (n % 5) == 0
      then print "Buzz"
      else print (show n)
    fizzbuzz (n + 1)

main =
  let _ = fizzbuzz 1
  0