diff options
| author | krasimir <krasimir@chalmers.se> | 2009-12-13 18:50:29 +0000 |
|---|---|---|
| committer | krasimir <krasimir@chalmers.se> | 2009-12-13 18:50:29 +0000 |
| commit | f85232947e74ee7ef8c7b0ad2338212e7e68f1be (patch) | |
| tree | 667b886a5e3a4b026a63d4e3597f32497d824761 /src/GF/Grammar/PatternMatch.hs | |
| parent | d88a865faff59c98fc91556ff8700b10ee5f2df8 (diff) | |
reorganize the directories under src, and rescue the JavaScript interpreter from deprecated
Diffstat (limited to 'src/GF/Grammar/PatternMatch.hs')
| -rw-r--r-- | src/GF/Grammar/PatternMatch.hs | 165 |
1 files changed, 0 insertions, 165 deletions
diff --git a/src/GF/Grammar/PatternMatch.hs b/src/GF/Grammar/PatternMatch.hs deleted file mode 100644 index b8f7eff7d..000000000 --- a/src/GF/Grammar/PatternMatch.hs +++ /dev/null @@ -1,165 +0,0 @@ ----------------------------------------------------------------------- --- | --- Module : PatternMatch --- Maintainer : AR --- Stability : (stable) --- Portability : (portable) --- --- > CVS $Date: 2005/10/12 12:38:29 $ --- > CVS $Author: aarne $ --- > CVS $Revision: 1.7 $ --- --- pattern matching for both concrete and abstract syntax. AR -- 16\/6\/2003 ------------------------------------------------------------------------------ - -module GF.Grammar.PatternMatch (matchPattern, - testOvershadow, - findMatch - ) where - -import GF.Data.Operations -import GF.Grammar.Grammar -import GF.Infra.Ident -import GF.Grammar.Macros -import GF.Grammar.Printer - -import Data.List -import Control.Monad -import Text.PrettyPrint -import Debug.Trace - -matchPattern :: [(Patt,Term)] -> Term -> Err (Term, Substitution) -matchPattern pts term = - if not (isInConstantForm term) - then Bad (render (text "variables occur in" <+> ppTerm Unqualified 0 term)) - else do - term' <- mkK term - errIn (render (text "trying patterns" <+> hsep (punctuate comma (map (ppPatt Unqualified 0 . fst) pts)))) $ - findMatch [([p],t) | (p,t) <- pts] [term'] - where - -- to capture all Str with string pattern matching - mkK s = case s of - C _ _ -> do - s' <- getS s - return (K (unwords s')) - _ -> return s - - getS s = case s of - K w -> return [w] - C v w -> liftM2 (++) (getS v) (getS w) - Empty -> return [] - _ -> Bad (render (text "cannot get string from" <+> ppTerm Unqualified 0 s)) - -testOvershadow :: [Patt] -> [Term] -> Err [Patt] -testOvershadow pts vs = do - let numpts = zip pts [0..] - let cases = [(p,EInt i) | (p,i) <- numpts] - ts <- mapM (liftM fst . matchPattern cases) vs - return [p | (p,i) <- numpts, notElem i [i | EInt i <- ts] ] - -findMatch :: [([Patt],Term)] -> [Term] -> Err (Term, Substitution) -findMatch cases terms = case cases of - [] -> Bad (render (text "no applicable case for" <+> hsep (punctuate comma (map (ppTerm Unqualified 0) terms)))) - (patts,_):_ | length patts /= length terms -> - Bad (render (text "wrong number of args for patterns :" <+> hsep (map (ppPatt Unqualified 0) patts) <+> - text "cannot take" <+> hsep (map (ppTerm Unqualified 0) terms))) - (patts,val):cc -> case mapM tryMatch (zip patts terms) of - Ok substs -> return (val, concat substs) - _ -> findMatch cc terms - -tryMatch :: (Patt, Term) -> Err [(Ident, Term)] -tryMatch (p,t) = do - t' <- termForm t - trym p t' - where - - isInConstantFormt = True -- tested already in matchPattern - trym p t' = - case (p,t') of - (_,(x,Empty,y)) -> trym p (x,K [],y) -- because "" = [""] = [] - (PW, _) | isInConstantFormt -> return [] -- optimization with wildcard - (PV x, _) | isInConstantFormt -> return [(x,t)] - (PString s, ([],K i,[])) | s==i -> return [] - (PInt s, ([],EInt i,[])) | s==i -> return [] - (PFloat s,([],EFloat i,[])) | s==i -> return [] --- rounding? - (PC p pp, ([], Con f, tt)) | - p `eqStrIdent` f && length pp == length tt -> - do matches <- mapM tryMatch (zip pp tt) - return (concat matches) - - (PP q p pp, ([], QC r f, tt)) | - -- q `eqStrIdent` r && --- not for inherited AR 10/10/2005 - p `eqStrIdent` f && length pp == length tt -> - do matches <- mapM tryMatch (zip pp tt) - return (concat matches) - ---- hack for AppPredef bug - (PP q p pp, ([], Q r f, tt)) | - -- q `eqStrIdent` r && --- - p `eqStrIdent` f && length pp == length tt -> - do matches <- mapM tryMatch (zip pp tt) - return (concat matches) - - (PR r, ([],R r',[])) | - all (`elem` map fst r') (map fst r) -> - do matches <- mapM tryMatch - [(p,snd a) | (l,p) <- r, let Just a = lookup l r'] - return (concat matches) - (PT _ p',_) -> trym p' t' - - (PAs x p',_) -> do - subst <- trym p' t' - return $ (x,t) : subst - - (PAlt p1 p2,_) -> checks [trym p1 t', trym p2 t'] - - (PNeg p',_) -> case tryMatch (p',t) of - Bad _ -> return [] - _ -> Bad (render (text "no match with negative pattern" <+> ppPatt Unqualified 0 p)) - - (PSeq p1 p2, ([],K s, [])) -> do - let cuts = [splitAt n s | n <- [0 .. length s]] - matches <- checks [mapM tryMatch [(p1,K s1),(p2,K s2)] | (s1,s2) <- cuts] - return (concat matches) - - (PRep p1, ([],K s, [])) -> checks [ - trym (foldr (const (PSeq p1)) (PString "") - [1..n]) t' | n <- [0 .. length s] - ] >> - return [] - - (PChar, ([],K [_], [])) -> return [] - (PChars cs, ([],K [c], [])) | elem c cs -> return [] - - _ -> Bad (render (text "no match in case expr for" <+> ppTerm Unqualified 0 t)) - -isInConstantForm :: Term -> Bool -isInConstantForm trm = case trm of - Cn _ -> True - Con _ -> True - Q _ _ -> True - QC _ _ -> True - Abs _ _ _ -> True - C c a -> isInConstantForm c && isInConstantForm a - App c a -> isInConstantForm c && isInConstantForm a - R r -> all (isInConstantForm . snd . snd) r - K _ -> True - Empty -> True - EInt _ -> True - _ -> False ---- isInArgVarForm trm - -varsOfPatt :: Patt -> [Ident] -varsOfPatt p = case p of - PV x -> [x] - PC _ ps -> concat $ map varsOfPatt ps - PP _ _ ps -> concat $ map varsOfPatt ps - PR r -> concat $ map (varsOfPatt . snd) r - PT _ q -> varsOfPatt q - _ -> [] - --- | to search matching parameter combinations in tables -isMatchingForms :: [Patt] -> [Term] -> Bool -isMatchingForms ps ts = all match (zip ps ts') where - match (PC c cs, (Cn d, ds)) = c == d && isMatchingForms cs ds - match _ = True - ts' = map appForm ts - |
