Haskell: read input character from console immediately, not after newline

Yes, it’s a bug. Here’s a workaround to save folks clicking and scrolling:

{-# LANGUAGE ForeignFunctionInterface #-}
import Data.Char
import Foreign.C.Types
getHiddenChar = fmap (chr.fromEnum) c_getch
foreign import ccall unsafe "conio.h getch"
  c_getch :: IO CInt

So you can replace calls to getChar with calls to getHiddenChar.

Note this is a workaround just for ghc/ghci on Windows. For example, winhugs doesn’t have the bug and this code doesn’t work in winhugs.

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