getCh

9.6の計算機プログラムの中でgetChという関数が出てきていて、コンパイルに通らないのでgetCharに置き換えてたんだけど、

< Page 90. The action getCh is no longer provided as a primitive in Hugs, but can be defined in Haskell as follows: >|haskell| import System.IO getCh :: IO Char getCh = do hSetEcho stdin False c <- getChar hSetEcho stdin True return c ||< This definition works with the Glasgow Haskell Compiler, but may not work with some Haskell systems, such as Hugs. >

えー。