使用GHC API

Question

当我试图做出typechecks Haskell的文件我使用GHC API的程序寻找阴谋包。我已经获得了类型检查，可以用于本地文件，但是我有一个特定的cabal软件包，我需要它也可以使用（这个可执行文件将是该软件包的一部分）。如何添加此导入依赖项？

我也试图与GHC命令行编译摸不着头脑，用ghc -package PKG-VER --make Test.hs -v但似乎只在本地目录进口的样子。

我当前的代码如下所示：

import   Control.Exception 
import   Control.Monad 
import   Control.Monad.State 
import   DynFlags 
import   Exception 
import   GHC 
import   GHC.Paths   (libdir) 
typecheck :: MonadIO m => [FilePath] -> FilePath -> m() 
typecheck otherincludes fp = 
    liftIO . defaultErrorHandler defaultLogAction . runGhc (Just libdir) $ do 
    dynflags <- getSessionDynFlags 
    void $ setSessionDynFlags dynflags { includePaths = otherIncludes ++ includePaths dynflags } 
    target <- guessTarget fp Nothing 
    setTargets [target] 
    void $ load LoadAllTargets 
    deps <- depanal [] False 
    forM_ deps $ \ms -> parseModule ms >>= typecheckModule 

Answer 1

我设法让你的代码读取和类型检查本身如下：

package Test where 
import   Control.Exception 
import   Control.Monad 
import   Control.Monad.State 
import   DynFlags 
import   Exception 
import   GHC 
import   GHC.Paths   (libdir) 
typecheck :: MonadIO m => [FilePath] -> FilePath -> m() 
typecheck otherincludes fp = 
    liftIO . defaultErrorHandler defaultLogAction . runGhc (Just libdir) $ do 
    dynflags <- getSessionDynFlags 
    void $ setSessionDynFlags dynflags { 
     includePaths = otherincludes ++ includePaths dynflags, 
     packageFlags = [ExposePackage "ghc"]} } 
    target <- guessTarget fp Nothing 
    setTargets [target] 
    void $ load LoadAllTargets 
    deps <- depanal [] False 
    forM_ deps $ \ms -> parseModule ms >>= typecheckModule 

这里是如何在ghci中运行：

$ ghci Test.hs -package ghc 
GHCi, version 7.4.1: http://www.haskell.org/ghc/ :? for help 
Loading package ghc-prim ... linking ... done. 
Loading package integer-gmp ... linking ... done. 
Loading package base ... linking ... done. 
Loading package array-0.4.0.0 ... linking ... done. 
Loading package deepseq-1.3.0.0 ... linking ... done. 
Loading package containers-0.4.2.1 ... linking ... done. 
Loading package filepath-1.3.0.0 ... linking ... done. 
Loading package old-locale-1.0.0.4 ... linking ... done. 
Loading package old-time-1.1.0.0 ... linking ... done. 
Loading package bytestring-0.9.2.1 ... linking ... done. 
Loading package unix-2.5.1.0 ... linking ... done. 
Loading package directory-1.1.0.2 ... linking ... done. 
Loading package pretty-1.1.1.0 ... linking ... done. 
Loading package process-1.1.0.1 ... linking ... done. 
Loading package Cabal-1.14.0 ... linking ... done. 
Loading package binary-0.5.1.0 ... linking ... done. 
Loading package bin-package-db-0.0.0.0 ... linking ... done. 
Loading package hoopl-3.8.7.3 ... linking ... done. 
Loading package hpc-0.5.1.1 ... linking ... done. 
Loading package template-haskell ... linking ... done. 
Loading package ghc-7.4.1 ... linking ... done. 
Ok, modules loaded: Test. 
Prelude Test> typecheck [] "Test.hs" 
Loading package transformers-0.3.0.0 ... linking ... done. 
Loading package mtl-2.1.1 ... linking ... done. 
Prelude Test> 

因此，关键似乎是在dynflags参数传递暴露包setSessionDynFlags。有关文档，请参阅DynFlags模块。