Shimuuar

import Data.Default
import Debug.Trace

data Proxy a = Proxy

class Magick a where
  magickStorage :: Proxy [a] -> String

instance Magick Int where
  magickStorage = const "Int"

Shimuuar

{-# LANGUAGE NoMonomorphismRestriction, BangPatterns #-}
module Main where

-- compile: ghc --make -main-is Prime.main Prime.hs -O2
-- $time ./Prime i 500000
-- ./Prime i 500000  4.35s user 0.00s system 99% cpu 4.453 total
-- ./Prime s 500000  7.69s user 0.03s system 99% cpu 7.726 total (!!!)
-- lookup OPT in comments about various optimization points

import System.Environment(getArgs)