GRE Vocabulary Prep

Word-of-the-Day.hs

{-# LANGUAGE Arrows,OverloadedStrings,BangPatterns #-}
module Main where

import System.Random       
import Control.Arrow
import Control.Monad
import Data.Monoid

import qualified Control.Category as Cat
import qualified Control.Foldl    as Fold
import qualified Data.Text        as Text
import qualified Data.Text.IO     as Text
import qualified Turtle
import Turtle(s,d,(%))
import Control.Foldl (Fold,FoldM)
import Data.Text (Text)

numWords :: Int {- determined emperically -}
numWords = 235886 

randomWord :: IO Text
randomWord =  do
  (idx,_) <- (pure (randomR (0,numWords))) <*> newStdGen
  (Turtle.ExitSuccess, out) <- Turtle.shellStrict (cmd idx) Turtle.empty
  return out
  where cmd = Turtle.format ("tail -n" %d% " /usr/share/dict/words | head -1")
main = randomWord >>= Text.putStr