我正在尝试使用haskell-src-exts包中的parseFile函数解析文件。 我正在尝试处理parseFile的输出,它当然是IO类型的,但我不知道如何处理IO类型。我发现了一个liftIO函数,但我不确定这是否是此情况的解决方案。以下是代码。
我希望能在
请注意,所有类型和数据构造函数可在http://hackage.haskell.org/packages/archive/haskell-src-exts/1.13.5/doc/html/Language-Haskell-Exts-Syntax.html中找到。谢谢!
import Language.Haskell.Exts.Syntax
import Language.Haskell.Exts
import Data.Map hiding (foldr, map)
import Control.Monad.Trans
increment :: Ord a => a -> Map a Int -> Map a Int
increment a = insertWith (+) a 1
fromName :: Name -> String
fromName (Ident s) = s
fromName (Symbol st) = st
fromQName :: QName -> String
fromQName (Qual _ fn) = fromName fn
fromQName (UnQual n) = fromName n
fromLiteral :: Literal -> String
fromLiteral (Int int) = show int
fromQOp :: QOp -> String
fromQOp (QVarOp qn) = fromQName qn
vars :: Exp -> Map String Int
vars (List (x:xs)) = vars x
vars (Lambda _ _ e1) = vars e1
vars (EnumFrom e1) = vars e1
vars (App e1 e2) = unionWith (+) (vars e1) (vars e2)
vars (Let _ e1) = vars e1
vars (NegApp e1) = vars e1
vars (Var qn) = increment (fromQName qn) empty
vars (Lit l) = increment (fromLiteral l) empty
vars (Paren e1) = vars e1
vars (InfixApp exp1 qop exp2) =
increment (fromQOp qop) $
unionWith (+) (vars exp1) (vars exp2)
match :: [Match] -> Map String Int
match rhss = foldr (unionWith (+) ) empty
(map (\(Match a b c d e f) -> rHs e) rhss)
rHS :: GuardedRhs -> Map String Int
rHS (GuardedRhs _ _ e1) = vars e1
rHs':: [GuardedRhs] -> Map String Int
rHs' gr = foldr (unionWith (+)) empty
(map (\(GuardedRhs a b c) -> vars c) gr)
rHs :: Rhs -> Map String Int
rHs (GuardedRhss gr) = rHs' gr
rHs (UnGuardedRhs e1) = vars e1
decl :: [Decl] -> Map String Int
decl decls = foldr (unionWith (+) ) empty
(map fun decls )
where fun (FunBind f) = match f
fun _ = empty
pMod' :: (ParseResult Module) -> Map String Int
pMod' (ParseOk (Module _ _ _ _ _ _ dEcl)) = decl dEcl
pMod :: FilePath -> Map String Int
pMod = pMod' . liftIO . parseFile
我希望能在
parseFile
的输出上使用pMod'
函数。请注意,所有类型和数据构造函数可在http://hackage.haskell.org/packages/archive/haskell-src-exts/1.13.5/doc/html/Language-Haskell-Exts-Syntax.html中找到。谢谢!