Beginning Haskell

Okey, it passed about a year I started learn and use F# and it's now time to learn Haskell. As usual, I started from the naive Fibonacci function:
module Fib where
fib :: Integer -> Integer
fib 0 = 0
fib 1 = 1
fib x = fib (x - 1) + fib (x - 2)
module Main where
import Fib
import System.TimeIt
main::IO()
main =
timeIt $ sequence_ [putStrLn $ "fib " ++ (show x) ++ " = " ++ (show $ fib x) | x <- [0..39]]
-- it results in ~14 seconds
view raw Fib.hs hosted with ❤ by GitHub
The performance in this particular algorithm is not fantastic, it's actually ~4 times slower than F#. It's OK for now.

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