Windows中具有GHCI的Haskell外部功能接口

首先，我指定使用Windows 10 64bit和Haskell Platform 8.0.1。

我尝试使用以下代码在Windows中使用Haskell的FFI。

import Control.Monad
import Data.Char
import Foreign.C

getCh :: IO Char
getCh = liftM (chr . fromEnum) c_getch
foreign import ccall unsafe "conio.h getch" c_getch :: IO CInt

main :: IO ()
main = getCh >>= \x -> print x

之后，我可以用ghc很好地编译

> ghc Examples.hs
[1 of 1] Compiling Main             ( Examples.hs, Examples.o )
Linking Examples.exe ...

并且它完全运行。

> Examples.exe
'1'

（当我运行它后键入1时）

但是，GHCI会出现问题。当我将其加载到ghci时，我收到了这些消息。

> ghci Examples.hs
GHCi, version 8.0.1: http://www.haskell.org/ghc/  :? for help
[1 of 1] Compiling Main             ( Examples.hs, interpreted )
Ok, modules loaded: Main.
*Main> main

ByteCodeLink: can't find label
During interactive linking, GHCi couldn't find the following symbol:
  getch
This may be due to you not asking GHCi to load extra object files,
archives or DLLs needed by your current session.  Restart GHCi, specifying
the missing library using the -L/path/to/object/dir and -lmissinglibname
flags, or simply by naming the relevant files on the GHCi command line.
Alternatively, this link failure might indicate a bug in GHCi.
If you suspect the latter, please send a bug report to:
  [email protected]

*Main>

我尝试加载“ missing library”，例如-lmsvcrt需要使用的“ ” conio.h，但结果悲观地相同。

> ghci -lmsvcrt Examples.hs
GHCi, version 8.0.1: http://www.haskell.org/ghc/  :? for help
[1 of 1] Compiling Main             ( Examples.hs, interpreted )
Ok, modules loaded: Main.
*Main> main

ByteCodeLink: can't find label
During interactive linking, GHCi couldn't find the following symbol:
  getch
This may be due to you not asking GHCi to load extra object files,
archives or DLLs needed by your current session.  Restart GHCi, specifying
the missing library using the -L/path/to/object/dir and -lmissinglibname
flags, or simply by naming the relevant files on the GHCi command line.
Alternatively, this link failure might indicate a bug in GHCi.
If you suspect the latter, please send a bug report to:
  [email protected]

*Main>

GHCI可能会加载该库，因为当我尝试加载错误的库时，ghci会输出有关该错误的信息。

我尝试了其他几种方法，例如使用ghci Examples.hs -fobject-code，ghci -lmsvcrt Examples.hs -fobject-code甚至

ghci Examples.hs "-luser32" "-lgdi32" "-lwinmm" "-ladvapi32" "-lshell32"
"-lshfolder" "-lwsock32" "-luser32" "-lshell32" "-lmsvcrt" "-lmingw32" 
"-lmingwex" "-luser32" "-lmingw32" "-lmingwex" "-lm" "-lwsock32" "-lgdi32" "-lwinmm"

在中找到的ghc Examples.hs -v5。

可悲的是，没有任何东西可用于我main，并且我找不到其他任何方式。

PS有没有人知道如何在Windows中使用hSetBuffering（它发布于8年前的ghc票号＃2189中。不是固定的吗？）