{-| Module : Idris.Elab.Clause Description : Code to elaborate clauses. License : BSD3 Maintainer : The Idris Community. -} {-# LANGUAGE PatternGuards #-} module Idris.Elab.Clause where import Idris.AbsSyntax import Idris.ASTUtils import Idris.Core.CaseTree import Idris.Core.Elaborate hiding (Tactic(..)) import Idris.Core.Evaluate import Idris.Core.TT import Idris.Core.Typecheck import Idris.Core.WHNF import Idris.Coverage import Idris.DataOpts import Idris.DeepSeq () import Idris.Delaborate import Idris.Docstrings hiding (Unchecked) import Idris.Elab.AsPat import Idris.Elab.Term import Idris.Elab.Transform import Idris.Elab.Type import Idris.Elab.Utils import Idris.Error import Idris.Options import Idris.Output (iWarn, pshow, sendHighlighting) import Idris.PartialEval import Idris.Termination import Idris.Transforms import Util.Pretty hiding ((<$>)) import Prelude hiding (id, (.)) import Control.Category import Control.DeepSeq import Control.Monad import qualified Control.Monad.State.Lazy as LState import Control.Monad.State.Strict as State import Data.List import Data.Maybe import Data.Word import Debug.Trace import Numeric -- | Elaborate a collection of left-hand and right-hand pairs - that is, a -- top-level definition. elabClauses :: ElabInfo -> FC -> FnOpts -> Name -> [PClause] -> Idris () elabClauses info' fc opts n_in cs = do let n = liftname info n_in info = info' { elabFC = Just fc } ctxt <- getContext ist <- getIState optimise <- getOptimise let petrans = PETransform `elem` optimise inacc <- map fst <$> fgetState (opt_inaccessible . ist_optimisation n) -- Check n actually exists, with no definition yet let tys = lookupTy n ctxt let reflect = Reflection `elem` opts when (reflect && FCReflection `notElem` idris_language_extensions ist) $ ierror $ At fc (Msg "You must turn on the FirstClassReflection extension to use %reflection") checkUndefined n ctxt unless (length tys > 1) $ do fty <- case tys of [] -> -- TODO: turn into a CAF if there's no arguments -- question: CAFs in where blocks? tclift $ tfail $ At fc (NoTypeDecl n) [ty] -> return ty let atys_in = map snd (getArgTys (normalise ctxt [] fty)) let atys = map (\x -> (x, isCanonical x ctxt)) atys_in cs_elab <- mapM (elabClause info opts) (zip [0..] cs) ctxt <- getContext -- pats_raw is the basic type checked version, no PE or forcing let optinfo = idris_optimisation ist let (pats_in, cs_full) = unzip cs_elab let pats_raw = map (simple_lhs ctxt) pats_in -- We'll apply forcing to the left hand side here, so that we don't -- do any unnecessary case splits let pats_forced = map (force_lhs optinfo) pats_raw logElab 3 $ "Elaborated patterns:\n" ++ show pats_raw logElab 5 $ "Forced patterns:\n" ++ show pats_forced solveDeferred fc n -- just ensure that the structure exists fmodifyState (ist_optimisation n) id addIBC (IBCOpt n) ist <- getIState ctxt <- getContext -- Don't apply rules if this is a partial evaluation definition, -- or we'll make something that just runs itself! let tpats = case specNames opts of Nothing -> transformPats ist pats_in _ -> pats_in -- If the definition is specialisable, this reduces the -- RHS pe_tm <- doPartialEval ist tpats let pats_pe = if petrans then map (force_lhs optinfo . simple_lhs ctxt) pe_tm else pats_forced let tcase = opt_typecase (idris_options ist) -- Look for 'static' names and generate new specialised -- definitions for them, as well as generating rewrite rules -- for partially evaluated definitions newrules <- if petrans then mapM (\ e -> case e of Left _ -> return [] Right (l, r) -> elabPE info fc n r) pats_pe else return [] -- Redo transforms with the newly generated transformations, so -- that the specialised application we've just made gets -- used in place of the general one ist <- getIState let pats_transformed = if petrans then transformPats ist pats_pe else pats_pe -- Summary of what's about to happen: Definitions go: -- -- pats_in -> pats -> pdef -> pdef' -- addCaseDef builds case trees from and -- pdef is the compile-time pattern definition, after forcing -- optimisation applied to LHS let pdef = map (\(ns, lhs, rhs) -> (map fst ns, lhs, rhs)) $ map debind pats_forced -- pdef_pe is the one which will get further optimised -- for run-time, with no forcing optimisation of the LHS because -- the affects erasure. Also, it's partially evaluated let pdef_pe = map debind pats_transformed logElab 5 $ "Initial typechecked patterns:\n" ++ show pats_raw logElab 5 $ "Initial typechecked pattern def:\n" ++ show pdef -- NOTE: Need to store original definition so that proofs which -- rely on its structure aren't affected by any changes to the -- inliner. Just use the inlined version to generate pdef' and to -- help with later inlinings. ist <- getIState numArgs <- tclift $ sameLength pdef case specNames opts of Just _ -> do logElab 3 $ "Partially evaluated:\n" ++ show pats_pe _ -> return () logElab 3 $ "Transformed:\n" ++ show pats_transformed erInfo <- getErasureInfo <$> getIState tree@(CaseDef scargs sc _) <- tclift $ simpleCase tcase (UnmatchedCase "Error") reflect CompileTime fc inacc atys pdef erInfo cov <- coverage pmissing <- if cov && not (hasDefault pats_raw) then do -- Generate clauses from the given possible cases missing <- genClauses fc n (map (\ (ns,tm,_) -> (ns, tm)) pdef) cs_full -- missing <- genMissing n scargs sc missing' <- checkPossibles info fc True n missing -- Filter out the ones which match one of the -- given cases (including impossible ones) logElab 2 $ "Must be unreachable (" ++ show (length missing') ++ "):\n" ++ showSep "\n" (map showTmImpls missing') ++ "\nAgainst: " ++ showSep "\n" (map (\t -> showTmImpls (delab ist t)) (map getLHS pdef)) -- filter out anything in missing' which is -- matched by any of clhs. This might happen since -- unification may force a variable to take a -- particular form, rather than force a case -- to be impossible. return missing' -- (filter (noMatch ist clhs) missing') else return [] let pcover = null pmissing -- pdef' is the version that gets compiled for run-time, -- so we start from the partially evaluated version pdef_in' <- applyOpts $ map (\(ns, lhs, rhs) -> (map fst ns, lhs, rhs)) pdef_pe ctxt <- getContext let pdef' = map (simple_rt ctxt) pdef_in' logElab 5 $ "After data structure transformations:\n" ++ show pdef' ist <- getIState let tot | pcover = Unchecked -- finish later | AssertTotal `elem` opts = Total [] | PEGenerated `elem` opts = Generated | otherwise = Partial NotCovering -- already know it's not total case tree of CaseDef _ _ [] -> return () CaseDef _ _ xs -> mapM_ (\x -> iWarn fc $ text "Unreachable case:" text (show (delab ist x)) ) xs let knowncovering = (pcover && cov) || AssertTotal `elem` opts let defaultcase = if knowncovering then STerm Erased else UnmatchedCase $ "*** " ++ show fc ++ ":unmatched case in " ++ show n ++ " ***" tree' <- tclift $ simpleCase tcase defaultcase reflect RunTime fc inacc atys pdef' erInfo logElab 3 $ "Unoptimised " ++ show n ++ ": " ++ show tree logElab 3 $ "Optimised: " ++ show tree' ctxt <- getContext ist <- getIState putIState (ist { idris_patdefs = addDef n (force pdef_pe, force pmissing) (idris_patdefs ist) }) let caseInfo = CaseInfo (inlinable opts) (inlinable opts) (dictionary opts) case lookupTyExact n ctxt of Just ty -> do ctxt' <- do ctxt <- getContext tclift $ addCasedef n erInfo caseInfo tcase defaultcase reflect (AssertTotal `elem` opts) atys inacc pats_forced pdef pdef' ty ctxt setContext ctxt' addIBC (IBCDef n) addDefinedName n setTotality n tot when (not reflect && PEGenerated `notElem` opts) $ do totcheck (fc, n) defer_totcheck (fc, n) when (tot /= Unchecked) $ addIBC (IBCTotal n tot) i <- getIState ctxt <- getContext case lookupDef n ctxt of (CaseOp _ _ _ _ _ cd : _) -> let (scargs, sc) = cases_compiletime cd in do let calls = map fst $ findCalls sc scargs -- let scg = buildSCG i sc scargs -- add SCG later, when checking totality logElab 2 $ "Called names: " ++ show calls -- if the definition is public, make sure -- it only uses public names nvis <- getFromHideList n case nvis of Just Public -> mapM_ (checkVisibility fc n Public Public) calls _ -> return () addCalls n calls let rig = if linearArg (whnfArgs ctxt [] ty) then Rig1 else RigW updateContext (setRigCount n (minRig ctxt rig calls)) addIBC (IBCCG n) _ -> return () return () -- addIBC (IBCTotal n tot) _ -> return () -- Check it's covering, if 'covering' option is used. Chase -- all called functions, and fail if any of them are also -- 'Partial NotCovering' when (CoveringFn `elem` opts) $ checkAllCovering fc [] n n -- Add the 'AllGuarded' flag if it's guaranteed that every -- 'Inf' argument will be guarded by constructors in the result -- (allows productivity check to go under this function) checkIfGuarded n -- If this has %static arguments, cache the names of functions -- it calls for partial evaluation later ist <- getIState let statics = case lookupCtxtExact n (idris_statics ist) of Just ns -> ns Nothing -> [] when (or statics) $ do getAllNames n return () where checkUndefined n ctxt = case lookupDef n ctxt of [] -> return () [TyDecl _ _] -> return () _ -> tclift $ tfail (At fc (AlreadyDefined n)) debind (Right (x, y)) = let (vs, x') = depat [] x (_, y') = depat [] y in (vs, x', y') debind (Left x) = let (vs, x') = depat [] x in (vs, x', Impossible) depat acc (Bind n (PVar rig t) sc) = depat ((n, t) : acc) (instantiate (P Bound n t) sc) depat acc x = (acc, x) getPVs (Bind x (PVar rig _) tm) = let (vs, tm') = getPVs tm in (x:vs, tm') getPVs tm = ([], tm) isPatVar vs (P Bound n _) = n `elem` vs isPatVar _ _ = False hasDefault cs | (Right (lhs, rhs) : _) <- reverse cs , (pvs, tm) <- getPVs (explicitNames lhs) , (f, args) <- unApply tm = all (isPatVar pvs) args hasDefault _ = False getLHS (_, l, _) = l -- Simplify the left hand side of a definition, to remove any lets -- that may have arisen during elaboration simple_lhs ctxt (Right (x, y)) = Right (Idris.Core.Evaluate.simplify ctxt [] x, y) simple_lhs ctxt t = t force_lhs opts (Right (x, y)) = Right (forceWith opts x, y) force_lhs opts t = t simple_rt ctxt (p, x, y) = (p, x, force (uniqueBinders p (rt_simplify ctxt [] y))) specNames [] = Nothing specNames (Specialise ns : _) = Just ns specNames (_ : xs) = specNames xs sameLength ((_, x, _) : xs) = do l <- sameLength xs let (_, as) = unApply x if (null xs || l == length as) then return (length as) else tfail (At fc (Msg "Clauses have differing numbers of arguments ")) sameLength [] = return 0 -- Partially evaluate, if the definition is marked as specialisable doPartialEval ist pats = case specNames opts of Nothing -> return pats Just ns -> case partial_eval (tt_ctxt ist) ns pats of Just t -> return t Nothing -> ierror (At fc (Msg "No specialisation achieved")) minRig :: Context -> RigCount -> [Name] -> RigCount minRig c minr [] = minr minRig c minr (r : rs) = case lookupRigCountExact r c of Nothing -> minRig c minr rs Just rc -> minRig c (min minr rc) rs forceWith :: Ctxt OptInfo -> Term -> Term forceWith opts lhs = -- trace (show lhs ++ "\n==>\n" ++ show (force lhs) ++ "\n----") $ force lhs where -- If there's forced arguments, erase them force ap@(App _ _ _) | (fn@(P _ c _), args) <- unApply ap, Just copt <- lookupCtxtExact c opts = let args' = eraseArg 0 (forceable copt) args in mkApp fn (map force args') force (App t f a) = App t (force f) (force a) -- We might have pat bindings, so go under them force (Bind n b sc) = Bind n b (force sc) -- Everything else, leave it alone force t = t eraseArg i fs (n : ns) | i `elem` fs = Erased : eraseArg (i + 1) fs ns | otherwise = n : eraseArg (i + 1) fs ns eraseArg i _ [] = [] -- | Find 'static' applications in a term and partially evaluate them. -- Return any new transformation rules elabPE :: ElabInfo -> FC -> Name -> Term -> Idris [(Term, Term)] -- Don't go deeper than 5 nested partially evaluated definitions in one go -- (make this configurable? It's a good limit for most cases, certainly for -- interfaces and polymorphic definitions, but maybe not for DSLs and -- interpreters in complicated cases. -- Possibly only worry about the limit if we've specialised the same function -- a number of times in one go.) elabPE info fc caller r | pe_depth info > 5 = return [] elabPE info fc caller r = do ist <- getIState let sa = filter (\ap -> fst ap /= caller) $ getSpecApps ist [] r rules <- mapM mkSpecialised sa return $ concat rules where -- Make a specialised version of the application, and -- add a PTerm level transformation rule, which is basically the -- new definition in reverse (before specialising it). -- RHS => LHS where implicit arguments are left blank in the -- transformation. -- Transformation rules are applied after every PClause elaboration mkSpecialised :: (Name, [(PEArgType, Term)]) -> Idris [(Term, Term)] mkSpecialised specapp_in = do ist <- getIState ctxt <- getContext (specTy, specapp) <- getSpecTy ist specapp_in let (n, newnm, specdecl) = getSpecClause ist specapp specTy let lhs = pe_app specdecl let rhs = pe_def specdecl let undef = case lookupDefExact newnm ctxt of Nothing -> True _ -> False logElab 5 $ show (newnm, undef, map (concreteArg ist) (snd specapp)) idrisCatch (if (undef && all (concreteArg ist) (snd specapp)) then do cgns <- getAllNames n -- on the RHS of the new definition, we should reduce -- everything that's not itself static (because we'll -- want to be a PE version of those next) let cgns' = filter (\x -> x /= n && notStatic ist x) cgns -- set small reduction limit on partial/productive things let maxred = case lookupTotal n ctxt of [Total _] -> 65536 [Productive] -> 16 _ -> 1 let specnames = mapMaybe (specName (pe_simple specdecl)) (snd specapp) descs <- mapM getStaticsFrom (map fst specnames) let opts = [Specialise ((if pe_simple specdecl then map (\x -> (x, Nothing)) cgns' else []) ++ (n, Just maxred) : specnames ++ concat descs)] logElab 3 $ "Specialising application: " ++ show specapp ++ "\n in \n" ++ show caller ++ "\n with \n" ++ show opts ++ "\nCalling: " ++ show cgns logElab 3 $ "New name: " ++ show newnm logElab 3 $ "PE definition type : " ++ (show specTy) ++ "\n" ++ show opts logElab 2 $ "PE definition " ++ show newnm ++ ":\n" ++ showSep "\n" (map (\ (lhs, rhs) -> (showTmImpls lhs ++ " = " ++ showTmImpls rhs)) (pe_clauses specdecl)) logElab 5 $ show n ++ " transformation rule: " ++ showTmImpls rhs ++ " ==> " ++ showTmImpls lhs elabType info defaultSyntax emptyDocstring [] fc opts newnm NoFC specTy let def = map (\(lhs, rhs) -> let lhs' = mapPT hiddenToPH $ stripUnmatchable ist lhs in PClause fc newnm lhs' [] rhs []) (pe_clauses specdecl) trans <- elabTransform info fc False rhs lhs elabClauses (info {pe_depth = pe_depth info + 1}) fc (PEGenerated:opts) newnm def return [trans] else return []) -- if it doesn't work, just don't specialise. Could happen for lots -- of valid reasons (e.g. local variables in scope which can't be -- lifted out). (\e -> do logElab 5 $ "Couldn't specialise: " ++ (pshow ist e) return []) hiddenToPH (PHidden _) = Placeholder hiddenToPH x = x specName simpl (ImplicitS _, tm) | (P Ref n _, _) <- unApply tm = Just (n, Just (if simpl then 1 else 0)) specName simpl (ExplicitS, tm) | (P Ref n _, _) <- unApply tm = Just (n, Just (if simpl then 1 else 0)) specName simpl (ConstraintS, tm) | (P Ref n _, _) <- unApply tm = Just (n, Just (if simpl then 1 else 0)) specName simpl _ = Nothing -- get the descendants of the name 'n' which are marked %static -- Marking a function %static essentially means it's used to construct -- programs, so should be evaluated by the partial evaluator getStaticsFrom :: Name -> Idris [(Name, Maybe Int)] getStaticsFrom n = do ns <- getAllNames n i <- getIState let statics = filter (staticFn i) ns return (map (\n -> (n, Nothing)) statics) staticFn :: IState -> Name -> Bool staticFn i n = case lookupCtxt n (idris_flags i) of [opts] -> elem StaticFn opts _ -> False notStatic ist n = case lookupCtxtExact n (idris_statics ist) of Just s -> not (or s) _ -> True concreteArg ist (ImplicitS _, tm) = concreteTm ist tm concreteArg ist (ExplicitS, tm) = concreteTm ist tm concreteArg ist _ = True concreteTm ist tm | (P _ n _, _) <- unApply tm = case lookupTy n (tt_ctxt ist) of [] -> False _ -> True concreteTm ist (Constant _) = True concreteTm ist (Bind n (Lam _ _) sc) = True concreteTm ist (Bind n (Pi _ _ _ _) sc) = True concreteTm ist (Bind n (Let _ _ _) sc) = concreteTm ist sc concreteTm ist _ = False -- get the type of a specialised application getSpecTy ist (n, args) = case lookupTy n (tt_ctxt ist) of [ty] -> let (specty_in, args') = specType args (explicitNames ty) specty = normalise (tt_ctxt ist) [] (finalise specty_in) t = mkPE_TyDecl ist args' (explicitNames specty) in return (t, (n, args')) -- (normalise (tt_ctxt ist) [] (specType args ty)) _ -> ifail $ "Ambiguous name " ++ show n ++ " (getSpecTy)" -- get the clause of a specialised application getSpecClause ist (n, args) specTy = let newnm = sUN ("PE_" ++ show (nsroot n) ++ "_" ++ qhash 5381 (showSep "_" (map showArg args))) in -- UN (show n ++ show (map snd args)) in (n, newnm, mkPE_TermDecl ist newnm n specTy args) where showArg (ExplicitS, n) = qshow n showArg (ImplicitS _, n) = qshow n showArg _ = "" qshow (Bind _ _ _) = "fn" qshow (App _ f a) = qshow f ++ qshow a qshow (P _ n _) = show n qshow (Constant c) = show c qshow _ = "" -- Simple but effective string hashing... -- Keep it to 32 bits for readability/debuggability qhash :: Word64 -> String -> String qhash hash [] = showHex (abs hash `mod` 0xffffffff) "" qhash hash (x:xs) = qhash (hash * 33 + fromIntegral(fromEnum x)) xs -- | Checks if the clause is a possible left hand side. -- NOTE: A lot of this is repeated for reflected definitions in Idris.Elab.Term -- One day, these should be merged, but until then remember that if you edit -- this you might need to edit the other version... checkPossible :: ElabInfo -> FC -> Bool -> Name -> PTerm -> Idris (Maybe PTerm) checkPossible info fc tcgen fname lhs_in = do ctxt <- getContext i <- getIState let lhs = addImplPat i lhs_in logElab 10 $ "Trying missing case: " ++ showTmImpls lhs -- if the LHS type checks, it is possible case elaborate (constraintNS info) ctxt (idris_datatypes i) (idris_name i) (sMN 0 "patLHS") infP initEState (erun fc (buildTC i info EImpossible [] fname (allNamesIn lhs_in) (infTerm lhs))) of OK (ElabResult lhs' _ _ ctxt' newDecls highlights newGName, _) -> do setContext ctxt' processTacticDecls info newDecls sendHighlighting highlights updateIState $ \i -> i { idris_name = newGName } let lhs_tm = normalise ctxt [] (orderPats (getInferTerm lhs')) let emptyPat = hasEmptyPat ctxt (idris_datatypes i) lhs_tm if emptyPat then do logElab 10 $ "Empty type in pattern " return Nothing else case recheck (constraintNS info) ctxt' [] (forget lhs_tm) lhs_tm of OK (tm, _, _) -> do logElab 10 $ "Valid " ++ show tm ++ "\n" ++ " from " ++ show lhs return (Just (delab' i tm True True)) err -> do logElab 10 $ "Conversion failure" return Nothing -- if it's a recoverable error, the case may become possible Error err -> do logLvl 10 $ "Impossible case " ++ (pshow i err) ++ "\n" ++ show (recoverableCoverage ctxt err, validCoverageCase ctxt err) -- tcgen means that it was generated by genClauses, -- so only looking for an error. Otherwise, it -- needs to be the right kind of error (a type mismatch -- in the same family). if tcgen then returnTm i err (recoverableCoverage ctxt err) else returnTm i err (validCoverageCase ctxt err || recoverableCoverage ctxt err) where returnTm i err True = do logLvl 10 $ "Possibly resolvable error on " ++ pshow i (fmap (normalise (tt_ctxt i) []) err) ++ " on " ++ showTmImpls lhs_in return $ Just lhs_in returnTm i err False = return $ Nothing -- Filter out the terms which are not well type left hand sides. Whenever we -- eliminate one, also eliminate later ones which match it without checking, -- because they're obviously going to have the same result checkPossibles :: ElabInfo -> FC -> Bool -> Name -> [PTerm] -> Idris [PTerm] checkPossibles info fc tcgen fname (lhs : rest) = do ok <- checkPossible info fc tcgen fname lhs i <- getIState -- Hypothesis: any we can remove will be within the next few, because -- leftmost patterns tend to change less -- Since the match could take a while if there's a lot of cases to -- check, just remove from the next batch let rest' = filter (\x -> not (qmatch x lhs)) (take 200 rest) ++ drop 200 rest restpos <- checkPossibles info fc tcgen fname rest' case ok of Nothing -> return restpos Just lhstm -> return (lhstm : restpos) where qmatch _ Placeholder = True qmatch (PApp _ f args) (PApp _ f' args') | length args == length args' = qmatch f f' && and (zipWith qmatch (map getTm args) (map getTm args')) qmatch (PRef _ _ n) (PRef _ _ n') = n == n' qmatch (PPair _ _ _ l r) (PPair _ _ _ l' r') = qmatch l l' && qmatch r r' qmatch (PDPair _ _ _ l t r) (PDPair _ _ _ l' t' r') = qmatch l l' && qmatch t t' && qmatch r r' qmatch x y = x == y checkPossibles _ _ _ _ [] = return [] findUnique :: Context -> Env -> Term -> [Name] findUnique ctxt env (Bind n b sc) = let rawTy = forgetEnv (map fstEnv env) (binderTy b) uniq = case check ctxt env rawTy of OK (_, UType UniqueType) -> True OK (_, UType NullType) -> True OK (_, UType AllTypes) -> True _ -> False in if uniq then n : findUnique ctxt ((n, RigW, b) : env) sc else findUnique ctxt ((n, RigW, b) : env) sc findUnique _ _ _ = [] -- | Return the elaborated LHS/RHS, and the original LHS with implicits added elabClause :: ElabInfo -> FnOpts -> (Int, PClause) -> Idris (Either Term (Term, Term), PTerm) elabClause info opts (_, PClause fc fname lhs_in [] PImpossible []) = do let tcgen = Dictionary `elem` opts i <- get let lhs = addImpl [] i lhs_in b <- checkPossible info fc tcgen fname lhs_in case b of Just _ -> tclift $ tfail (At fc (Msg $ show lhs_in ++ " is a valid case")) Nothing -> do ptm <- mkPatTm lhs_in logElab 5 $ "Elaborated impossible case " ++ showTmImpls lhs ++ "\n" ++ show ptm return (Left ptm, lhs) elabClause info opts (cnum, PClause fc fname lhs_in_as withs rhs_in_as whereblock_as) = do push_estack fname False ctxt <- getContext let (lhs_in, rhs_in, whereblock) = desugarAs lhs_in_as rhs_in_as whereblock_as -- Build the LHS as an "Infer", and pull out its type and -- pattern bindings i <- getIState inf <- isTyInferred fname -- Check if we have "with" patterns outside of "with" block when (isOutsideWith lhs_in && (not $ null withs)) $ ierror (At (fromMaybe NoFC $ highestFC lhs_in_as) (Elaborating "left hand side of " fname Nothing (Msg "unexpected patterns outside of \"with\" block"))) -- get the parameters first, to pass through to any where block let fn_ty = case lookupTy fname ctxt of [t] -> t _ -> error "Can't happen (elabClause function type)" let fn_is = case lookupCtxt fname (idris_implicits i) of [t] -> t _ -> [] let norm_ty = normalise ctxt [] fn_ty let params = getParamsInType i [] fn_is norm_ty let tcparams = getTCParamsInType i [] fn_is norm_ty let lhs = mkLHSapp $ stripLinear i $ stripUnmatchable i $ propagateParams i params norm_ty (allNamesIn lhs_in) (addImplPat i lhs_in) -- let lhs = mkLHSapp $ -- propagateParams i params fn_ty (addImplPat i lhs_in) logElab 10 (show (params, fn_ty) ++ " " ++ showTmImpls (addImplPat i lhs_in)) logElab 5 ("LHS: " ++ show opts ++ "\n" ++ show fc ++ " " ++ showTmImpls lhs) logElab 4 ("Fixed parameters: " ++ show params ++ " from " ++ showTmImpls lhs_in ++ "\n" ++ show (fn_ty, fn_is)) ((ElabResult lhs' dlhs [] ctxt' newDecls highlights newGName, probs, inj), _) <- tclift $ elaborate (constraintNS info) ctxt (idris_datatypes i) (idris_name i) (sMN 0 "patLHS") infP initEState (do res <- errAt "left hand side of " fname Nothing (erun (fromMaybe NoFC $ highestFC lhs_in_as) (buildTC i info ELHS opts fname (allNamesIn lhs_in) (infTerm lhs))) probs <- get_probs inj <- get_inj return (res, probs, inj)) setContext ctxt' processTacticDecls info newDecls sendHighlighting highlights updateIState $ \i -> i { idris_name = newGName } when inf $ addTyInfConstraints fc (map (\(x,y,_,_,_,_,_) -> (x,y)) probs) let lhs_tm = orderPats (getInferTerm lhs') let lhs_ty = getInferType lhs' let static_names = getStaticNames i lhs_tm logElab 3 ("Elaborated: " ++ show lhs_tm) logElab 3 ("Elaborated type: " ++ show lhs_ty) logElab 5 ("Injective: " ++ show fname ++ " " ++ show inj) -- If we're inferring metavariables in the type, don't recheck, -- because we're only doing this to try to work out those metavariables ctxt <- getContext (clhs_c, clhsty) <- if not inf then recheckC_borrowing False (PEGenerated `notElem` opts) [] (constraintNS info) fc id [] lhs_tm else return (lhs_tm, lhs_ty) let clhs = normalise ctxt [] clhs_c let borrowed = borrowedNames [] clhs -- These are the names we're not allowed to use on the RHS, because -- they're UniqueTypes and borrowed from another function. when (not (null borrowed)) $ logElab 5 ("Borrowed names on LHS: " ++ show borrowed) logElab 3 ("Normalised LHS: " ++ showTmImpls (delabMV i clhs)) rep <- useREPL when rep $ do addInternalApp (fc_fname fc) (fst . fc_start $ fc) (delabMV i clhs) -- TODO: Should use span instead of line and filename? addIBC (IBCLineApp (fc_fname fc) (fst . fc_start $ fc) (delabMV i clhs)) logElab 5 ("Checked " ++ show clhs ++ "\n" ++ show clhsty) -- Elaborate where block ist <- getIState ctxt <- getContext windex <- getName let decls = nub (concatMap declared whereblock) let defs = nub (decls ++ concatMap defined whereblock) let newargs_all = pvars ist lhs_tm -- Unique arguments must be passed to the where block explicitly -- (since we can't control "usage" easlily otherwise). Remove them -- from newargs here let uniqargs = findUnique ctxt [] lhs_tm let newargs = filter (\(n,_) -> n `notElem` uniqargs) newargs_all let winfo = (pinfo info newargs defs windex) { elabFC = Just fc } let wb = map (mkStatic static_names) $ map (expandImplementationScope ist decorate newargs defs) $ map (expandParamsD False ist decorate newargs defs) whereblock -- Split the where block into declarations with a type, and those -- without -- Elaborate those with a type *before* RHS, those without *after* let (wbefore, wafter) = sepBlocks wb logElab 5 $ "Where block:\n " ++ show wbefore ++ "\n" ++ show wafter mapM_ (rec_elabDecl info EAll winfo) wbefore -- Now build the RHS, using the type of the LHS as the goal. i <- getIState -- new implicits from where block logElab 5 (showTmImpls (expandParams decorate newargs defs (defs \\ decls) rhs_in)) let rhs = rhs_trans info $ addImplBoundInf i (map fst newargs_all) (defs \\ decls) (expandParams decorate newargs defs (defs \\ decls) rhs_in) logElab 2 $ "RHS: " ++ show (map fst newargs_all) ++ " " ++ showTmImpls rhs ctxt <- getContext -- new context with where block added logElab 5 "STARTING CHECK" ((rhsElab, defer, holes, is, probs, ctxt', newDecls, highlights, newGName), _) <- tclift $ elaborate (constraintNS info) ctxt (idris_datatypes i) (idris_name i) (sMN 0 "patRHS") clhsty initEState (do pbinds ist lhs_tm -- proof search can use explicitly written names mapM_ addPSname (allNamesIn lhs_in) ulog <- getUnifyLog traceWhen ulog ("Setting injective: " ++ show (nub (tcparams ++ inj))) $ mapM_ setinj (nub (tcparams ++ inj)) setNextName (ElabResult _ _ is ctxt' newDecls highlights newGName) <- errAt "right hand side of " fname (Just clhsty) (erun fc (build i winfo ERHS opts fname rhs)) errAt "right hand side of " fname (Just clhsty) (erun fc $ psolve lhs_tm) tt <- get_term aux <- getAux let (tm, ds) = runState (collectDeferred (Just fname) (map fst $ case_decls aux) ctxt tt) [] probs <- get_probs hs <- get_holes return (tm, ds, hs, is, probs, ctxt', newDecls, highlights, newGName)) setContext ctxt' processTacticDecls info newDecls sendHighlighting highlights updateIState $ \i -> i { idris_name = newGName } when inf $ addTyInfConstraints fc (map (\(x,y,_,_,_,_,_) -> (x,y)) probs) logElab 3 "DONE CHECK" logElab 3 $ "---> " ++ show rhsElab ctxt <- getContext let rhs' = rhsElab when (not (null defer)) $ logElab 2 $ "DEFERRED " ++ show (map (\ (n, (_,_,t,_)) -> (n, t)) defer) -- If there's holes, set the metavariables as undefinable def' <- checkDef info fc (\n -> Elaborating "deferred type of " n Nothing) (null holes) defer let def'' = map (\(n, (i, top, t, ns)) -> (n, (i, top, t, ns, False, null holes))) def' addDeferred def'' mapM_ (\(n, _) -> addIBC (IBCDef n)) def'' when (not (null def')) $ do mapM_ defer_totcheck (map (\x -> (fc, fst x)) def'') -- Now the remaining deferred (i.e. no type declarations) clauses -- from the where block mapM_ (rec_elabDecl info EAll winfo) wafter mapM_ (elabCaseBlock winfo opts) is ctxt <- getContext logElab 5 "Rechecking" logElab 6 $ " ==> " ++ show (forget rhs') (crhs, crhsty) -- if there's holes && deferred things, it's okay -- but we'll need to freeze the definition and not -- allow the deferred things to be definable -- (this is just to allow users to inspect intermediate -- things) <- if (null holes || null def') && not inf then recheckC_borrowing True (PEGenerated `notElem` opts) borrowed (constraintNS info) fc id [] rhs' else return (rhs', clhsty) logElab 6 $ " ==> " ++ showEnvDbg [] crhsty ++ " against " ++ showEnvDbg [] clhsty -- If there's holes, make sure this definition is frozen when (not (null holes)) $ do logElab 5 $ "Making " ++ show fname ++ " frozen due to " ++ show holes setAccessibility fname Frozen ctxt <- getContext let constv = next_tvar ctxt tit <- typeInType case LState.runStateT (convertsC ctxt [] crhsty clhsty) (constv, []) of OK (_, cs) -> when (PEGenerated `notElem` opts && not tit) $ do addConstraints fc cs mapM_ (\c -> addIBC (IBCConstraint fc c)) (snd cs) logElab 6 $ "CONSTRAINTS ADDED: " ++ show cs ++ "\n" ++ show (clhsty, crhsty) return () Error e -> ierror (At fc (CantUnify False (clhsty, Nothing) (crhsty, Nothing) e [] 0)) i <- getIState checkInferred fc (delab' i crhs True True) rhs -- if the function is declared '%error_reverse', -- then we'll try running it in reverse to improve error messages -- Also if the type is '%error_reverse' and the LHS is smaller than -- the RHS let (ret_fam, _) = unApply (getRetTy crhsty) rev <- case ret_fam of P _ rfamn _ -> case lookupCtxt rfamn (idris_datatypes i) of [TI _ _ dopts _ _ _] -> return (DataErrRev `elem` dopts && size clhs <= size crhs) _ -> return False _ -> return False when (rev || ErrorReverse `elem` opts) $ do addIBC (IBCErrRev (crhs, clhs)) addErrRev (crhs, clhs) when (rev || ErrorReduce `elem` opts) $ do addIBC (IBCErrReduce fname) addErrReduce fname pop_estack return (Right (clhs, crhs), lhs) where pinfo :: ElabInfo -> [(Name, PTerm)] -> [Name] -> Int -> ElabInfo pinfo info ns ds i = let newps = params info ++ ns dsParams = map (\n -> (n, map fst newps)) ds newb = addAlist dsParams (inblock info) in info { params = newps, inblock = newb, liftname = id -- (\n -> case lookupCtxt n newb of -- Nothing -> n -- _ -> MN i (show n)) . l } -- Find the variable names which appear under a 'Ownership.Read' so that -- we know they can't be used on the RHS borrowedNames :: [Name] -> Term -> [Name] borrowedNames env (App _ (App _ (P _ (NS (UN lend) [owner]) _) _) arg) | owner == txt "Ownership" && (lend == txt "lend" || lend == txt "Read") = getVs arg where getVs (V i) = [env!!i] getVs (App _ f a) = nub $ getVs f ++ getVs a getVs _ = [] borrowedNames env (App _ f a) = nub $ borrowedNames env f ++ borrowedNames env a borrowedNames env (Bind n b sc) = nub $ borrowedB b ++ borrowedNames (n:env) sc where borrowedB (Let _ t v) = nub $ borrowedNames env t ++ borrowedNames env v borrowedB b = borrowedNames env (binderTy b) borrowedNames _ _ = [] mkLHSapp t@(PRef _ _ _) = PApp fc t [] mkLHSapp t = t decorate (NS x ns) = NS (SN (WhereN cnum fname x)) ns decorate x = SN (WhereN cnum fname x) sepBlocks bs = sepBlocks' [] bs where sepBlocks' ns (d@(PTy _ _ _ _ _ n _ t) : bs) = let (bf, af) = sepBlocks' (n : ns) bs in (d : bf, af) sepBlocks' ns (d@(PClauses _ _ n _) : bs) | not (n `elem` ns) = let (bf, af) = sepBlocks' ns bs in (bf, d : af) sepBlocks' ns (b : bs) = let (bf, af) = sepBlocks' ns bs in (b : bf, af) sepBlocks' ns [] = ([], []) -- term is not within "with" block isOutsideWith :: PTerm -> Bool isOutsideWith (PApp _ (PRef _ _ (SN (WithN _ _))) _) = False isOutsideWith _ = True elabClause info opts (_, PWith fc fname lhs_in withs wval_in pn_in withblock) = do ctxt <- getContext -- Build the LHS as an "Infer", and pull out its type and -- pattern bindings i <- getIState -- get the parameters first, to pass through to any where block let fn_ty = case lookupTy fname ctxt of [t] -> t _ -> error "Can't happen (elabClause function type)" let fn_is = case lookupCtxt fname (idris_implicits i) of [t] -> t _ -> [] let params = getParamsInType i [] fn_is (normalise ctxt [] fn_ty) let lhs = stripLinear i $ stripUnmatchable i $ propagateParams i params fn_ty (allNamesIn lhs_in) (addImplPat i lhs_in) logElab 2 ("LHS: " ++ show lhs) (ElabResult lhs' dlhs [] ctxt' newDecls highlights newGName, _) <- tclift $ elaborate (constraintNS info) ctxt (idris_datatypes i) (idris_name i) (sMN 0 "patLHS") infP initEState (errAt "left hand side of with in " fname Nothing (erun (fromMaybe NoFC $ highestFC lhs_in) (buildTC i info ELHS opts fname (allNamesIn lhs_in) (infTerm lhs))) ) setContext ctxt' processTacticDecls info newDecls sendHighlighting highlights updateIState $ \i -> i { idris_name = newGName } ctxt <- getContext let lhs_tm = orderPats (getInferTerm lhs') let lhs_ty = getInferType lhs' let ret_ty = getRetTy (explicitNames (normalise ctxt [] lhs_ty)) let static_names = getStaticNames i lhs_tm logElab 5 (show lhs_tm ++ "\n" ++ show static_names) (clhs_c, clhsty) <- recheckC (constraintNS info) fc id [] lhs_tm let clhs = normalise ctxt [] clhs_c logElab 5 ("Checked " ++ show clhs) let bargs = getPBtys (explicitNames (normalise ctxt [] lhs_tm)) wval <- case wval_in of Placeholder -> ierror $ At fc $ Msg "No expression for the with block to inspect.\nYou need to replace the _ with an expression." _ -> return $ rhs_trans info $ addImplBound i (map fst bargs) wval_in logElab 5 ("Checking " ++ showTmImpls wval) -- Elaborate wval in this context ((wvalElab, defer, is, ctxt', newDecls, highlights, newGName), _) <- tclift $ elaborate (constraintNS info) ctxt (idris_datatypes i) (idris_name i) (sMN 0 "withRHS") (bindTyArgs PVTy bargs infP) initEState (do pbinds i lhs_tm -- proof search can use explicitly written names mapM_ addPSname (allNamesIn lhs_in) setNextName -- TODO: may want where here - see winfo abpve (ElabResult _ d is ctxt' newDecls highlights newGName) <- errAt "with value in " fname Nothing (erun fc (build i info ERHS opts fname (infTerm wval))) erun fc $ psolve lhs_tm tt <- get_term return (tt, d, is, ctxt', newDecls, highlights, newGName)) setContext ctxt' processTacticDecls info newDecls sendHighlighting highlights updateIState $ \i -> i { idris_name = newGName } def' <- checkDef info fc iderr True defer let def'' = map (\(n, (i, top, t, ns)) -> (n, (i, top, t, ns, False, True))) def' addDeferred def'' mapM_ (elabCaseBlock info opts) is let wval' = wvalElab logElab 5 ("Checked wval " ++ show wval') ctxt <- getContext (cwval, cwvalty) <- recheckC (constraintNS info) fc id [] (getInferTerm wval') let cwvaltyN = explicitNames (normalise ctxt [] cwvalty) let cwvalN = explicitNames (normalise ctxt [] cwval) logElab 3 ("With type " ++ show cwvalty ++ "\nRet type " ++ show ret_ty) -- We're going to assume the with type is not a function shortly, -- so report an error if it is (you can't match on a function anyway -- so this doesn't lose anything) case getArgTys cwvaltyN of [] -> return () (_:_) -> ierror $ At fc (WithFnType cwvalty) let pvars = map fst (getPBtys cwvalty) -- we need the unelaborated term to get the names it depends on -- rather than a de Bruijn index. let pdeps = usedNamesIn pvars i (delab i cwvalty) let (bargs_pre, bargs_post) = split pdeps bargs [] let mpn = case pn_in of Nothing -> Nothing Just (n, nfc) -> Just (uniqueName n (map fst bargs)) -- Highlight explicit proofs sendHighlighting [(fc, AnnBoundName n False) | (n, fc) <- maybeToList pn_in] logElab 10 ("With type " ++ show (getRetTy cwvaltyN) ++ " depends on " ++ show pdeps ++ " from " ++ show pvars) logElab 10 ("Pre " ++ show bargs_pre ++ "\nPost " ++ show bargs_post) windex <- getName -- build a type declaration for the new function: -- (ps : Xs) -> (withval : cwvalty) -> (ps' : Xs') -> ret_ty let wargval = getRetTy cwvalN let wargtype = getRetTy cwvaltyN let wargname = sMN windex "warg" logElab 5 ("Abstract over " ++ show wargval ++ " in " ++ show wargtype) let wtype = bindTyArgs (flip (Pi RigW Nothing) (TType (UVar [] 0))) (bargs_pre ++ (wargname, wargtype) : map (abstract wargname wargval wargtype) bargs_post ++ case mpn of Just pn -> [(pn, mkApp (P Ref eqTy Erased) [wargtype, wargtype, P Bound wargname Erased, wargval])] Nothing -> []) (substTerm wargval (P Bound wargname wargtype) ret_ty) logElab 3 ("New function type " ++ show wtype) let wname = SN (WithN windex fname) let imps = getImps wtype -- add to implicits context putIState (i { idris_implicits = addDef wname imps (idris_implicits i) }) let statics = getStatics static_names wtype logElab 5 ("Static positions " ++ show statics) i <- getIState putIState (i { idris_statics = addDef wname statics (idris_statics i) }) addIBC (IBCDef wname) addIBC (IBCImp wname) addIBC (IBCStatic wname) def' <- checkDef info fc iderr True [(wname, (-1, Nothing, wtype, []))] let def'' = map (\(n, (i, top, t, ns)) -> (n, (i, top, t, ns, False, True))) def' addDeferred def'' -- in the subdecls, lhs becomes: -- fname pats | wpat [rest] -- ==> fname' ps wpat [rest], match pats against toplevel for ps wb <- mapM (mkAuxC mpn wname lhs (map fst bargs_pre) (map fst bargs_post)) withblock logElab 3 ("with block " ++ show wb) setFlags wname [Inlinable] when (AssertTotal `elem` opts) $ setFlags wname [Inlinable, AssertTotal] i <- getIState let rhstrans' = updateWithTerm i mpn wname lhs (map fst bargs_pre) (map fst (bargs_post)) . rhs_trans info mapM_ (rec_elabDecl info EAll (info { rhs_trans = rhstrans' })) wb -- rhs becomes: fname' ps_pre wval ps_post Refl let rhs = PApp fc (PRef fc [] wname) (map (pexp . (PRef fc []) . fst) bargs_pre ++ pexp wval : (map (pexp . (PRef fc []) . fst) bargs_post) ++ case mpn of Nothing -> [] Just _ -> [pexp (PApp NoFC (PRef NoFC [] eqCon) [ pimp (sUN "A") Placeholder False , pimp (sUN "x") Placeholder False ])]) logElab 5 ("New RHS " ++ showTmImpls rhs) ctxt <- getContext -- New context with block added i <- getIState ((rhsElab, defer, is, ctxt', newDecls, highlights, newGName), _) <- tclift $ elaborate (constraintNS info) ctxt (idris_datatypes i) (idris_name i) (sMN 0 "wpatRHS") clhsty initEState (do pbinds i lhs_tm setNextName (ElabResult _ d is ctxt' newDecls highlights newGName) <- erun fc (build i info ERHS opts fname rhs) psolve lhs_tm tt <- get_term return (tt, d, is, ctxt', newDecls, highlights, newGName)) setContext ctxt' processTacticDecls info newDecls sendHighlighting highlights updateIState $ \i -> i { idris_name = newGName } ctxt <- getContext let rhs' = rhsElab def' <- checkDef info fc iderr True defer let def'' = map (\(n, (i, top, t, ns)) -> (n, (i, top, t, ns, False, True))) def' addDeferred def'' mapM_ (elabCaseBlock info opts) is logElab 5 ("Checked RHS " ++ show rhs') (crhs, crhsty) <- recheckC (constraintNS info) fc id [] rhs' return (Right (clhs, crhs), lhs) where getImps (Bind n (Pi _ _ _ _) t) = pexp Placeholder : getImps t getImps _ = [] mkAuxC pn wname lhs ns ns' (PClauses fc o n cs) = do cs' <- mapM (mkAux pn wname lhs ns ns') cs return $ PClauses fc o wname cs' mkAuxC pn wname lhs ns ns' d = return d mkAux pn wname toplhs ns ns' (PClause fc n tm_in (w:ws) rhs wheres) = do i <- getIState let tm = addImplPat i tm_in logElab 2 ("Matching " ++ showTmImpls tm ++ " against " ++ showTmImpls toplhs) case matchClause i toplhs tm of Left (a,b) -> ifail $ show fc ++ ":with clause does not match top level" Right mvars -> do logElab 3 ("Match vars : " ++ show mvars) lhs <- updateLHS n pn wname mvars ns ns' (fullApp tm) w return $ PClause fc wname lhs ws rhs wheres mkAux pn wname toplhs ns ns' (PWith fc n tm_in (w:ws) wval pn' withs) = do i <- getIState let tm = addImplPat i tm_in logElab 2 ("Matching " ++ showTmImpls tm ++ " against " ++ showTmImpls toplhs) withs' <- mapM (mkAuxC pn wname toplhs ns ns') withs case matchClause i toplhs tm of Left (a,b) -> trace ("matchClause: " ++ show a ++ " =/= " ++ show b) (ifail $ show fc ++ "with clause does not match top level") Right mvars -> do lhs <- updateLHS n pn wname mvars ns ns' (fullApp tm) w return $ PWith fc wname lhs ws wval pn' withs' mkAux pn wname toplhs ns ns' c = ifail $ show fc ++ ":badly formed with clause" -- ns, arguments which don't depend on the with argument -- ns', arguments which do updateLHS n pn wname mvars ns_in ns_in' (PApp fc (PRef fc' hls' n') args) w = let ns = map (keepMvar (map fst mvars) fc') ns_in ns' = map (keepMvar (map fst mvars) fc') ns_in' in return $ substMatches mvars $ PApp fc (PRef fc' [] wname) (map pexp ns ++ pexp w : (map pexp ns') ++ case pn of Nothing -> [] Just pnm -> [pexp (PRef fc [] pnm)]) updateLHS n pn wname mvars ns_in ns_in' tm w = updateLHS n pn wname mvars ns_in ns_in' (PApp fc tm []) w -- Only keep a var as a pattern variable in the with block if it's -- matched in the top level pattern keepMvar mvs fc v | v `elem` mvs = PRef fc [] v | otherwise = Placeholder updateWithTerm :: IState -> Maybe Name -> Name -> PTerm -> [Name] -> [Name] -> PTerm -> PTerm updateWithTerm ist pn wname toplhs ns_in ns_in' tm = mapPT updateApp tm where currentFn fname (PAlternative _ _ as) | Just tm <- getApp as = tm where getApp (tm@(PApp _ (PRef _ _ f) _) : as) | f == fname = Just tm getApp (_ : as) = getApp as getApp [] = Nothing currentFn _ tm = tm updateApp wtm@(PWithApp fcw tm_in warg) = let tm = currentFn fname tm_in in case matchClause ist toplhs tm of Left _ -> PElabError (Msg (show fc ++ ":with application does not match top level ")) Right mvars -> let ns = map (keepMvar (map fst mvars) fcw) ns_in ns' = map (keepMvar (map fst mvars) fcw) ns_in' wty = lookupTyExact wname (tt_ctxt ist) res = substMatches mvars $ PApp fcw (PRef fcw [] wname) (map pexp ns ++ pexp warg : (map pexp ns') ++ case pn of Nothing -> [] Just pnm -> [pexp (PRef fc [] pnm)]) in case wty of Nothing -> res -- can't happen! Just ty -> addResolves ty res updateApp tm = tm addResolves ty (PApp fc f args) = PApp fc f (addResolvesArgs fc ty args) addResolves ty tm = tm -- if an argument's type is an interface, and is otherwise to -- be inferred, then resolve it with implementation search -- This is something of a hack, because matching on the top level -- application won't find this information for us addResolvesArgs :: FC -> Term -> [PArg] -> [PArg] addResolvesArgs fc (Bind n (Pi _ _ ty _) sc) (a : args) | (P _ cn _, _) <- unApply ty, getTm a == Placeholder = case lookupCtxtExact cn (idris_interfaces ist) of Just _ -> a { getTm = PResolveTC fc } : addResolvesArgs fc sc args Nothing -> a : addResolvesArgs fc sc args addResolvesArgs fc (Bind n (Pi _ _ ty _) sc) (a : args) = a : addResolvesArgs fc sc args addResolvesArgs fc _ args = args fullApp (PApp _ (PApp fc f args) xs) = fullApp (PApp fc f (args ++ xs)) fullApp x = x split [] rest pre = (reverse pre, rest) split deps ((n, ty) : rest) pre | n `elem` deps = split (deps \\ [n]) rest ((n, ty) : pre) | otherwise = split deps rest ((n, ty) : pre) split deps [] pre = (reverse pre, []) abstract wn wv wty (n, argty) = (n, substTerm wv (P Bound wn wty) argty) -- | Apply a transformation to all RHSes and nested RHSs mapRHS :: (PTerm -> PTerm) -> PClause -> PClause mapRHS f (PClause fc n lhs args rhs ws) = PClause fc n lhs args (f rhs) (map (mapRHSdecl f) ws) mapRHS f (PWith fc n lhs args warg prf ws) = PWith fc n lhs args (f warg) prf (map (mapRHSdecl f) ws) mapRHS f (PClauseR fc args rhs ws) = PClauseR fc args (f rhs) (map (mapRHSdecl f) ws) mapRHS f (PWithR fc args warg prf ws) = PWithR fc args (f warg) prf (map (mapRHSdecl f) ws) mapRHSdecl :: (PTerm -> PTerm) -> PDecl -> PDecl mapRHSdecl f (PClauses fc opt n cs) = PClauses fc opt n (map (mapRHS f) cs) mapRHSdecl f t = t