Guess Number Game [Multi Language Exercise.. not about line count]

guess.hs

-- this Haskell version is not quite the same as the Nim and Racket versions since I am pulling in a Random
-- number to be guessed, rather than hardcoding the number as seen on Nim and Racket versions on line 3. I am also
-- adding comments to the functions in this Haskell version. This might prompt me to go through and revamp other
-- solutions in the future.

import System.Random
import System.Environment
import Text.Regex
import Text.Regex.Base

-- strint converts a string to an integer, defaulting to 0 if the string doesn't represent a valid integer.
strint :: String -> Integer
strint x = do
  if Nothing == (matchOnce (makeRegex "^[0-9]+$" :: Regex) x)
  then 0
  else (read x :: Integer)

guess :: Integer -> IO ()
guess x = do
  putStrLn "Guess a number from 1 to 20. [0 to quit]"
  i <- getLine
  let answer = strint i
  if answer == 0
    then putStrLn "Bye!!"
    else do
      if answer == x
        then putStrLn "Thats Right"
        else
          do
            if answer > x
              then putStrLn "No. Try a lower number"
            else putStrLn "No. Try a higher number"
            guess x

main :: IO ()
main = do
  x <- randomRIO (1,20)
  guess x

guess.nim

import strutils

const answer = 0b1011

proc getInput(): (int, bool) =
    var rawInput: TaintedString
    try:
        rawInput = stdin.readLine
        let intInput = parseInt(rawInput)
        return (intInput, false)
    except ValueError:
        if rawInput == "x":
            return (0, true)
    return (0, false)

proc game() =
    block game:
        while true:
            echo "Guess a number between 1 and 10:"
            let (input, exit) = getInput()
            if exit:
                echo "ok exiting guessing game"
                break game
            case input:
                of 1..(answer - 1):
                    echo "Try a higher number"
                of (answer + 1)..20:
                    echo "Try a lower number"
                of answer:
                    echo format("You are right!! The answer is $1", input)
                    break game
                else:
                    echo "invalid number. 1 - 20"

game()

guess.rkt

#lang racket

(define answer #b10100)

(define (RUN)
  (define rv #f)
  (define player-input (question))
  (define guess (string->number player-input))
  (when (not (number? guess))
    (when (not(string=? player-input "x"))
      (displayln (format "You guessed a non number value: ~a" player-input))
      (set! rv #t)))
  (when (number? guess)
    (when (and (<= guess 20) (>= guess 1))
      (when (= guess answer)
        (displayln (format "You are right!!! The answer was ~a" player-input))
        (set! rv #f))
      (when (< guess answer)
        (displayln "Try a higher number")
        (set! rv #t))
      (when (> guess answer)
        (displayln "Try a lower number")
        (set! rv #t)))
    (when (or (> guess 20) (< guess 1))
      (displayln (format "You need to choose a number between 1 and 20. Try again :)"))
      (set! rv #t)))
  rv)

(define (question)
  (display (format "~a" "Pick a number from 1 - 20: "))
  (define input (read-line))
  input)

; game is the loop the runs the game until the answer is found.
(define (game bool)
  (when bool
    (define continue? (RUN))
    (game continue?)))

(game #t)