inline-c:"`type`无法在外国电话中编组"

Question

设置

AC枚举类型由c2hs呈现到Haskell中,完成Storable正确编译的实例(TypesC2Hs.chs).我将这个不合格的导入到我为inline-ccontext(Internal.hs)指定的模块中..hs由c2hs生成的模块和Internal.hs导入的模块,InlineC.hs另一个inline-c模块包含C调用的quasiquotes.

TypesC2Hs.hs ------------- 
    |                    |
    V                    V
Internal.hs -------> InlineC.hs

题

InlineC.hs 抱怨这种类型无法编组:"外国声明中不可接受的参数类型:'DMBoundaryType'无法在外部调用中编组时检查声明:"

到底是怎么回事？这是第一次inline-c给我这个错误的类型.

我应该注意,其他类型不需要直接解除引用,例如newtype DM = DM (Ptr DM) deriving Storable,使用上述方法可以正常工作.

提前致谢

---

TypesC2Hs.chs

{# enum DMBoundaryType as DMBoundaryType {underscoreToCase} deriving (Eq, Show) #}

instance Storable DMBoundaryType where
  sizeOf _ = {# sizeof DMBoundaryType #}
  alignment _ = {# alignof DMBoundaryType #}
  peek = peek
  poke = poke

Internal.hs

{-# LANGUAGE QuasiQuotes, TemplateHaskell ,GeneralizedNewtypeDeriving, StandaloneDeriving ,DeriveDataTypeable, DataKinds, OverloadedStrings #-}

module Internal where

import TypesC2Hs

import qualified Language.C.Inline         as C
import qualified Language.C.Types          as CT
import           Language.C.Inline.Context

import qualified Language.Haskell.TH       as TH

import           Data.Monoid               ((<>), mempty)
import qualified Data.Map                  as Map


ctx :: Context
ctx = baseCtx <> funCtx <> vecCtx <> bsCtx <> pctx where
  pctx = mempty {ctxTypesTable = typesTable}


typesTable :: Map.Map CT.TypeSpecifier TH.TypeQ  
typesTable = Map.fromList
              [ (CT.TypeName "DMBoundaryType", [t| DMBoundaryType |])  ]

InlineC.hs

dmdaCreate1d0' cc bx m dof s =
   withPtr ( \ dm -> [C.exp|int{DMDACreate1d($(int c),
                                              $(DMBoundaryType bx),
                                              $(PetscInt m),
                                              $(PetscInt dof),
                                              $(PetscInt s),
                                              NULL,
                                              $(DM* dm))}|]  )
  where c = unComm cc

Answer 1

C enum不是可编组的外来类型,这是编译器试图告诉你的.要解决它,将其作为CInt使用传递fromEnum(看起来c2hs现在通过钩子支持它,但我从未尝试过.)