hermit-0.1.8.0: examples/fib-stream/Fib.hs

module Main where

import Prelude hiding ((+),map,(!!))
import Nat
import Stream

import Data.Function(fix)

fib :: Nat -> Nat
fib Zero             = Zero
fib (Succ Zero)      = Succ Zero
fib (Succ (Succ n))  = fib (Succ n) + fib n

wrap :: Stream a -> (Nat -> a)
wrap s n = s !! n

unwrap :: (Nat -> a) -> Stream a
unwrap f = map f nats

main :: IO ()
main = print (fromNat $ fib $ toNat 30)