HaRe-0.6: refactorer/RefacRemoveField.hs
-----------------------------------------------------------------------------
-- |
-- Module : RefacRemoveField
-- Copyright : (c) Christopher Brown 2007
--
-- Maintainer : cmb21@kent.ac.uk
-- Stability : provisional
-- Portability : portable
--
-- This module contains a transformation for HaRe.
-- Remove a field from a constructor and resolve
-- pattern matching by placing references to said
-- field by calls to error.
-----------------------------------------------------------------------------
module RefacRemoveField where
import PrettyPrint
import PrettyPrint
import PosSyntax
import AbstractIO
import Maybe
import TypedIds
import UniqueNames hiding (srcLoc)
import PNT
import TiPNT
import List
import RefacUtils hiding (getParams)
import PFE0 (findFile)
import MUtils (( # ))
import RefacLocUtils
import System
import IO
import Char
refacRemoveField args
= do
let
fileName = args!!0
pos = args!!1
row = read (args!!2)::Int
col = read (args!!3)::Int
AbstractIO.putStrLn "refacRemoveField"
modInfo@(inscps, exps, mod, tokList) <- parseSourceFile (fileName)
case checkCursor fileName row col mod of
Left errMsg -> do error errMsg
Right dat ->
do
let res = locToPNT fileName (row, col) mod
let res2 = locToPN fileName (row, col) mod
let decs = hsDecls mod
let datDec = definingDecls [res2] decs False True
let datName = (declToName (head datDec))
let datPNT = (declToPNT (head datDec))
-- if the field in question is a record we must get
-- the name of the record...
((_,m), (newToks, newMod)) <- applyRefac (removeField datName datPNT res pos tokList)
(Just (inscps, exps, mod, tokList)) fileName
writeRefactoredFiles False [((fileName, m), (newToks, newMod))]
AbstractIO.putStrLn "Completed.\n"
checkCursor :: String -> Int -> Int -> HsModuleP -> Either String HsDeclP
checkCursor fileName row col mod
= case locToTypeDecl of
Nothing -> Left ("Invalid cursor position. Please place cursor at the beginning of the constructor name!")
Just decl@(Dec (HsDataDecl loc c tp xs _)) -> Right decl
where
locToTypeDecl = find (definesTypeCon (locToPNT fileName (row, col) mod)) (hsModDecls mod)
-- definesTypeCon pnt (Dec (HsDataDecl loc c tp xs _))
-- = isDataCon pnt && (findPNT pnt tp)
definesTypeCon pnt (Dec (HsDataDecl _ _ _ i _))
= isDataCon pnt && (findPNT pnt i)
definesTypeCon pnt _ = False
removeField datName datPNT pnt pos tok (_, _, t)
= do
let fType = getField pnt ((read pos)::Int) t
let fName = typToPNT (convertBang fType)
newMod <- removingField pnt pos t
d <- checkPat2 datName pnt pos newMod
newMod' <- removingFieldInPat datName pnt pos tok d
if d /= newMod
then do
newD' <- addDecl newMod' Nothing ([errorDecl], Nothing) True
dataType <- getDataType datPNT newD'
newTypedMod <- cleanTypeSigs fType fName datPNT datName pnt dataType newD'
return newTypedMod
else do
dataType <- getDataType datPNT newMod'
newTypedMod <- cleanTypeSigs fType fName datPNT datName pnt dataType newMod'
return newTypedMod
where
errorDecl = (Dec (HsFunBind loc0
[HsMatch loc0 (nameToPNT "errorData")
listOfPats
(HsBody (createFunc (nameToPNT ("error" ++ datName)) listOfExps)) []]))
listOfPats = nameToPat "field" : (nameToPat "dat" : [nameToPat "function"])
listOfExps = [Exp (HsId (HsVar (nameToPNT "(\"the binding for \" ++ field ++ \" in a pattern binding involving \" ++ dat ++ \" has been removed in function \" ++ function)"
)))]
convertBang (HsUnBangedType t) = t
convertBang (HsBangedType t) = t
getField pnt pos
= (fromMaybe (error "not a valid field to remove!")).(applyTU (once_tdTU (failTU `adhocTU` inDatDeclaration)))
where
inDatDeclaration (dat@(HsConDecl _ _ _ i ts)::HsConDeclP)
| pnt == i
= Just (ts !! (pos-1))
inDatDeclaration x = Nothing
flatternTApp :: HsTypeP -> [HsTypeP]
flatternTApp (Typ (HsTyFun t1 t2)) = flatternTApp t1 ++ flatternTApp t2
flatternTApp (Typ (HsTyApp t1 t2)) = flatternTApp t1 ++ flatternTApp t2
flatternTApp x = [x]
getDataType datPNT t
= applyTU (once_tdTU (failTU `adhocTU` inDatDeclaration)) t
where
inDatDeclaration (dat@(Dec (HsDataDecl a b tp c d))::HsDeclP)
| (defineLoc datPNT == (defineLoc.typToPNT.(ghead "inDatDeclaration").flatternTApp) tp)
= return dat
inDatDeclaration d = fail ""
flatternTApp :: HsTypeP -> [HsTypeP]
flatternTApp (Typ (HsTyFun t1 t2)) = flatternTApp t1 ++ flatternTApp t2
flatternTApp (Typ (HsTyApp t1 t2)) = flatternTApp t1 ++ flatternTApp t2
flatternTApp x = [x]
cleanTypeSigs fType fName datPNT datName pnt dataType t
= applyTP (full_buTP (idTP `adhocTP` inDatDeclaration)) t
where
inDatDeclaration (dat@(Dec (HsDataDecl a b tp c d))::HsDeclP)
| (defineLoc datPNT == (defineLoc.typToPNT.(ghead "inDatDeclaration").flatternTApp) tp) &&
(redunParam (tail (flatternTApp tp)) c)
=
-- update the data declaration with the type removed!
update dat (Dec (HsDataDecl a b (createDataFunc ((typToPNT.(ghead "inDatDeclaration").flatternTApp) tp)
( (tail (flatternTApp tp)) <-> (convertBang fType))) c d)) dat
inDatDeclaration (dat@(Dec (HsTypeSig s is c t))::HsDeclP)
| datName `elem` (map (pNTtoName.typToPNT) (flatternTApp t) )
= do
let res = changeType t dataType
if res == t
then return dat
else update dat (Dec (HsTypeSig s is c res)) dat
inDatDeclaration t =return t
changeType :: HsTypeP -> HsDeclP -> HsTypeP
changeType t@(Typ (HsTyFun t1 t2)) x
= (Typ (HsTyFun (changeType t1 x) (changeType t2 x)))
changeType t@(Typ (HsTyApp t1 t2)) (Dec (HsDataDecl a b tp c d))
| (defineLoc datPNT) == (defineLoc (convertToCon t1)) &&
((pNTtoName fName) `elem` (map (pNTtoName.typToPNT) (flatternTApp t))) &&
isLower (head (pNTtoName fName)) &&
(redunParam (tail (flatternTApp tp)) c)
= (createDataFunc ((typToPNT.(ghead "inDatDeclaration").flatternTApp) t)
( ( (tail (flatternTApp t)) <-> (convertBang fType))))
changeType t _ = t
convertToCon :: HsTypeP -> PNT
convertToCon (Typ (HsTyFun t1 t2)) = convertToCon t1
convertToCon (Typ (HsTyApp t1 t2)) = convertToCon t1
convertToCon (Typ (HsTyCon t1)) = t1
convertToCon t = defaultPNT
-- (<->) :: Term t => [a] -> a -> [a]
(<->) [] _ = []
(<->) (x:xs) y
| (pNTtoName (typToPNT x)) == (pNTtoName (typToPNT y)) = (xs <-> y)
| otherwise = x : (xs <-> y)
-- convertBangs :: [HsBangType t] -> [HsTypeP]
redunParam [] _ = False
redunParam xs (cs)
= length (filter id (map (inT cs) (map (pNTtoName.typToPNT) xs))) == 1
inT2 [] _ = [False]
inT2 ((HsConDecl s i c p types) :cs) x
= ((x `elem` (map (pNTtoName.typToPNT) (map convertBang types))) : (cs `inT2` x))
inT x y = (not.or) (x `inT2` y)
flatternTApp :: HsTypeP -> [HsTypeP]
flatternTApp (Typ (HsTyFun t1 t2)) = flatternTApp t1 ++ flatternTApp t2
flatternTApp (Typ (HsTyApp t1 t2)) = flatternTApp t1 ++ flatternTApp t2
flatternTApp x = [x]
removingField pnt pos t
= applyTP (stop_tdTP (failTP `adhocTP` inDat)) t
where
inDat (dat@(HsConDecl s i c p types)::HsConDeclP)
| p == pnt = do
r <- update dat (HsConDecl s i c p (newTypes types (read pos::Int))) dat
return r
inDat (dat@(HsRecDecl s i c p types)::HsConDeclP)
| p == pnt = do
r <- update dat (HsRecDecl s i c p (newRecTypes types (read pos::Int))) dat
return r
inDat _ = fail ""
newRecTypes :: (Eq a) => [([a], b)] -> Int -> [([a], b)]
newRecTypes xs i = newRecTypes' xs i 1
where
newRecTypes' :: (Eq a) => [([a], b)] -> Int -> Int -> [([a], b)]
newRecTypes' [] i n = error "Please select a valid field position for this constructor!"
newRecTypes' ((x,y):xs) i n
| i >= n && i < (n+(length x)) = case newTypes' x i n of
[] -> xs
x -> (x,y) : xs
| otherwise = (x,y) : (newRecTypes' xs i (n+(length x)))
newTypes :: [a] -> Int -> [a] -- -> [HsBangType HsTypeP]
newTypes xs i = newTypes' xs i 1
newTypes' :: [a] -> Int -> Int -> [a]
newTypes' [] _ _ = error "Please select a valid field position for this constructor!"
newTypes' (x:xs) i n
| n == i = xs
| otherwise = x : (newTypes' xs i (n+1))
removingFieldInPat datName pnt pos tok t
= applyTP (stop_tdTP (failTP `adhocTP` inPat)) t
where
inPat d@(Dec _::HsDeclP)
= do
d' <- checkPat1 pnt pos d
d'' <- checkCall pnt pos d'
return d''
where
-- checkPat :: (Term t) => PNT -> String -> t -> HsPatP
checkPat1 pnt pos t
= applyTP (full_tdTP (idTP `adhocTP` inP)) t
inP pat@(Pat (HsPApp i p))
| (defineLoc i) == (defineLoc pnt) = RefacUtils.delete (p !! ((read pos::Int)-1)) pat
inP x = return x
checkCall pnt pos t
= applyTP (stop_tdTP (failTP `adhocTP` conApp)) t
-- a constructor application...
conApp exp@(Exp (HsApp e1 e2))
| defineLoc pnt == (defineLoc.expToPNT.(ghead "inE").flatternApp) exp
= RefacUtils.delete ((tail (flatternApp exp)) !! ((read pos::Int)-1)) exp
conApp _ = mzero
flatternApp :: HsExpP -> [HsExpP]
flatternApp (Exp (HsApp e1 e2)) = flatternApp e1 ++ flatternApp e2
flatternApp x = [x]
(!-) :: Int -> Int -> [a] -> [a]
(!-) _ _ [] = []
(!-) n pos (x:xs)
| n == pos = xs
| otherwise = x : (!-) n (pos + 1) xs
newPats :: [HsPatP] -> Int -> Int -> [HsPatP]
newPats (p:ps) pos n
| n == pos = ps
| otherwise = p : (newPats ps pos (n+1))
-- inPat x = fail ""
checkPat2 datName pnt pos t
= applyTP (stop_tdTP (failTP `adhocTP` inPat)) t
where
inPat d@(Dec _::HsDeclP)
= do
d'' <- addCall (declToName d) pnt pos d
return d''
addCall funcName pnt pos t
= applyTP (stop_tdTP (failTP `adhocTP` (inE funcName))) t
-- a name associated to a pattern binding somewhere...
inE funcName exp@(Exp (HsId (HsVar x)))
| (findPatBind pnt x (read pos::Int) t)
= update exp (Exp (HsApp (Exp (HsApp (Exp (HsApp (nameToExp ("error" ++ datName))
(nameToExp ("\"" ++ (pNTtoName x) ++ "\""))))
(nameToExp ("\"" ++ (pNTtoName pnt) ++ "\""))))
(nameToExp ("\"" ++ funcName ++ "\"")))) exp
inE _ x = mzero
findPatBind :: (Term t) => PNT -> PNT -> Int -> t -> Bool
findPatBind pnt x pos
= (fromMaybe False).(applyTU (once_tdTU (failTU `adhocTU` inBind)))
where
inBind (dat@(Pat (HsPApp i types))::HsPatP)
| pnt == i && checkInTypes x (types!!(pos-1)) = Just True
inBind _ = Nothing
checkInTypes x (Pat (HsPId (HsVar typePnt)))
| defineLoc x == defineLoc typePnt = True
checkInTypes _ x = False
-- thePNT id = (PNT (PN (UnQual id) (G (PlainModule "unknown") id (N (Just loc0)))) (Type (TypeInfo (Just Primitive) [] [])) (N (Just loc0)))