ghc-mod/Language/Haskell/GhcMod/Browse.hs

129 lines
4.7 KiB
Haskell

module Language.Haskell.GhcMod.Browse (browseModule, browse) where
import Control.Applicative
import Control.Monad (void)
import Data.Char
import Data.List
import Data.Maybe (catMaybes)
import DataCon (dataConRepType)
import FastString (mkFastString)
import GHC
import Panic(throwGhcException)
import Language.Haskell.GhcMod.Doc (showUnqualifiedPage)
import Language.Haskell.GhcMod.GHCApi
import Language.Haskell.GhcMod.Types
import Name
import Outputable
import TyCon
import Type
import Var
----------------------------------------------------------------
-- | Getting functions, classes, etc from a module.
-- If 'detailed' is 'True', their types are also obtained.
-- If 'operators' is 'True', operators are also returned.
browseModule :: Options
-> Cradle
-> ModuleString -- ^ A module name. (e.g. \"Data.List\")
-> IO String
browseModule opt cradle mdlName = convert opt . sort <$> withGHCDummyFile (browse opt cradle mdlName)
-- | Getting functions, classes, etc from a module.
-- If 'detailed' is 'True', their types are also obtained.
-- If 'operators' is 'True', operators are also returned.
browse :: Options
-> Cradle
-> ModuleString -- ^ A module name. (e.g. \"Data.List\")
-> Ghc [String]
browse opt cradle mdlName = do
void $ initializeFlagsWithCradle opt cradle [] False
getModule >>= getModuleInfo >>= listExports
where
getModule = findModule mdlname mpkgid `gcatch` fallback
mdlname = mkModuleName mdlName
mpkgid = mkFastString <$> packageId opt
listExports Nothing = return []
listExports (Just mdinfo) = processExports opt mdinfo
-- findModule works only for package modules, moreover,
-- you cannot load a package module. On the other hand,
-- to browse a local module you need to load it first.
-- If CmdLineError is signalled, we assume the user
-- tried browsing a local module.
fallback (CmdLineError _) = loadAndFind
fallback e = throwGhcException e
loadAndFind = do
setTargetFiles [mdlName]
checkSlowAndSet
void $ load LoadAllTargets
findModule mdlname Nothing
processExports :: Options -> ModuleInfo -> Ghc [String]
processExports opt minfo = mapM (showExport opt minfo) $ removeOps $ modInfoExports minfo
where
removeOps
| operators opt = id
| otherwise = filter (isAlpha . head . getOccString)
showExport :: Options -> ModuleInfo -> Name -> Ghc String
showExport opt minfo e = do
mtype' <- mtype
return $ concat $ catMaybes [mqualified, Just $ formatOp $ getOccString e, mtype']
where
mqualified = (moduleNameString (moduleName $ nameModule e) ++ ".") `justIf` qualified opt
mtype
| detailed opt = do
tyInfo <- modInfoLookupName minfo e
-- If nothing found, load dependent module and lookup global
tyResult <- maybe (inOtherModule e) (return . Just) tyInfo
dflag <- getSessionDynFlags
return $ do
typeName <- tyResult >>= showThing dflag
(" :: " ++ typeName) `justIf` detailed opt
| otherwise = return Nothing
formatOp nm@(n:_)
| isAlpha n = nm
| otherwise = "(" ++ nm ++ ")"
formatOp "" = error "formatOp"
inOtherModule :: Name -> Ghc (Maybe TyThing)
inOtherModule nm = getModuleInfo (nameModule nm) >> lookupGlobalName nm
justIf :: a -> Bool -> Maybe a
justIf x True = Just x
justIf _ False = Nothing
showThing :: DynFlags -> TyThing -> Maybe String
showThing dflag (AnId i) = Just $ formatType dflag varType i
showThing dflag (ADataCon d) = Just $ formatType dflag dataConRepType d
showThing _ (ATyCon t) = unwords . toList <$> tyType t
where
toList t' = t' : getOccString t : map getOccString (tyConTyVars t)
showThing _ _ = Nothing
formatType :: NamedThing a => DynFlags -> (a -> Type) -> a -> String
formatType dflag f x = showOutputable dflag (removeForAlls $ f x)
tyType :: TyCon -> Maybe String
tyType typ
| isAlgTyCon typ
&& not (isNewTyCon typ)
&& not (isClassTyCon typ) = Just "data"
| isNewTyCon typ = Just "newtype"
| isClassTyCon typ = Just "class"
| isSynTyCon typ = Just "type"
| otherwise = Nothing
removeForAlls :: Type -> Type
removeForAlls ty = removeForAlls' ty' tty'
where
ty' = dropForAlls ty
tty' = splitFunTy_maybe ty'
removeForAlls' :: Type -> Maybe (Type, Type) -> Type
removeForAlls' ty Nothing = ty
removeForAlls' ty (Just (pre, ftype))
| isPredTy pre = mkFunTy pre (dropForAlls ftype)
| otherwise = ty
showOutputable :: Outputable a => DynFlags -> a -> String
showOutputable dflag = unwords . lines . showUnqualifiedPage dflag . ppr