ghc-mod/Language/Haskell/GhcMod/Browse.hs
2014-04-23 16:37:24 +09:00

151 lines
5.5 KiB
Haskell

module Language.Haskell.GhcMod.Browse (
browseModule
, browse
, browseAll)
where
import Control.Applicative ((<$>))
import Control.Monad (void)
import Data.Char (isAlpha)
import Data.List (sort)
import Data.Maybe (catMaybes)
import FastString (mkFastString)
import GHC (Ghc, GhcException(CmdLineError), ModuleInfo, Name, TyThing, DynFlags, Type, TyCon, Module)
import qualified GHC as G
import Language.Haskell.GhcMod.Doc (showPage, showOneLine, styleUnqualified)
import Language.Haskell.GhcMod.GHCApi
import Language.Haskell.GhcMod.Gap
import Language.Haskell.GhcMod.Types
import Name (getOccString)
import Outputable (ppr, Outputable)
import Panic (throwGhcException)
import TyCon (isAlgTyCon)
import Type (dropForAlls, splitFunTy_maybe, mkFunTy, isPredTy)
----------------------------------------------------------------
-- | 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 = withGHC' $ do
void $ initializeFlagsWithCradle opt cradle [] False
browse opt 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
-> ModuleString -- ^ A module name. (e.g. \"Data.List\")
-> Ghc String
browse opt mdlName = do
convert opt . sort <$> (getModule >>= G.getModuleInfo >>= listExports)
where
getModule = G.findModule mdlname mpkgid `G.gcatch` fallback
mdlname = G.mkModuleName mdlName
mpkgid = mkFastString <$> 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]
void $ G.load G.LoadAllTargets
G.findModule mdlname Nothing
processExports :: Options -> ModuleInfo -> Ghc [String]
processExports opt minfo = mapM (showExport opt minfo) $ removeOps $ G.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 = (G.moduleNameString (G.moduleName $ G.nameModule e) ++ ".") `justIf` qualified opt
mtype
| detailed opt = do
tyInfo <- G.modInfoLookupName minfo e
-- If nothing found, load dependent module and lookup global
tyResult <- maybe (inOtherModule e) (return . Just) tyInfo
dflag <- G.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 = G.getModuleInfo (G.nameModule nm) >> G.lookupGlobalName nm
justIf :: a -> Bool -> Maybe a
justIf x True = Just x
justIf _ False = Nothing
showThing :: DynFlags -> TyThing -> Maybe String
showThing dflag tything = showThing' dflag (fromTyThing tything)
showThing' :: DynFlags -> GapThing -> Maybe String
showThing' dflag (GtA a) = Just $ formatType dflag a
showThing' _ (GtT t) = unwords . toList <$> tyType t
where
toList t' = t' : getOccString t : map getOccString (G.tyConTyVars t)
showThing' _ _ = Nothing
formatType :: DynFlags -> Type -> String
formatType dflag a = showOutputable dflag (removeForAlls a)
tyType :: TyCon -> Maybe String
tyType typ
| isAlgTyCon typ
&& not (G.isNewTyCon typ)
&& not (G.isClassTyCon typ) = Just "data"
| G.isNewTyCon typ = Just "newtype"
| G.isClassTyCon typ = Just "class"
| G.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 . showPage dflag styleUnqualified . ppr
----------------------------------------------------------------
-- | Browsing all functions in all system/user modules.
browseAll :: DynFlags -> Ghc [(String,String)]
browseAll dflag = do
ms <- G.packageDbModules True
is <- mapM G.getModuleInfo ms
return $ concatMap (toNameModule dflag) (zip ms is)
toNameModule :: DynFlags -> (Module, Maybe ModuleInfo) -> [(String,String)]
toNameModule _ (_,Nothing) = []
toNameModule dflag (m,Just inf) = map (\name -> (toStr name, mdl)) names
where
mdl = G.moduleNameString (G.moduleName m)
names = G.modInfoExports inf
toStr = showOneLine dflag styleUnqualified . ppr