Question

使用cabal，我尝试在Haskell Platform 2012.2.0.0（Windows XP）上安装了酸状态，但是出现了以下错误：

src-win32\FileIO.hs:43:5:
    Not in scope: catchIO Perhaps you meant `catch' (imported from Prelude)

src-win32\FileIO.hs:55:6:
    Not in scope: tryE Perhaps you meant `try' (imported from Control.Exception.Extensible)

src-win32\FileIO.hs:56:6:
    Not in scope: tryE
    Perhaps you meant `try' (imported from Control.Exception.Extensible)
cabal: Error: some packages failed to install:
acid-state-0.8.1 failed during the building phase. The exception was:
ExitFailure 1

Answer 1

当转到可扩展的例外系统时，经常会出现这种麻烦。 tryE和catchIO是标准样板;他们只是专注catch和try来使用SomeException和IOException

 import Control.Exception.Extensible(try,throw)
 import Control.Exception(SomeException,IOException)
 import qualified Control.Exception as E 
 tryE :: IO a -> IO (Either SomeException a)
 tryE = try
 catchIO :: IO a -> (IOException -> IO a) -> IO a
 catchIO = E.catch

所以做cabal unpack acid-state，并用this替换src-win32 / FileIO.hs，它在第18ff行https://gist.github.com/4032603上定义它们然后从外部目录执行cabal install ，带有acid-state.cabal文件的那个。

可能还有一些额外的错误，因为我现在无法测试它。正如Paul R.所说，当你编译它时，将其发送给维护者。该软件包维护得很多，但看起来他们需要Windows测试人员。酸态肯定是值得的。您还应该尝试examples /目录中的一些模块，这些模块在任何情况下都是一个很好的教程。如果你有更多麻烦回写，我们可以一起设计一个合适的补丁文件。

无法在Haskell Platform 2012.2.0.0（Windows XP）上安装cabal-acid酸状态

1 个答案: