forked from GitHub/gf-core
446 lines
21 KiB
Haskell
446 lines
21 KiB
Haskell
----------------------------------------------------------------------
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-- |
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-- Maintainer : Krasimir Angelov
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-- Stability : (stable)
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-- Portability : (portable)
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--
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-- Converting SimpleGFC grammars to fast nonerasing MCFG grammar.
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--
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-- the resulting grammars might be /very large/
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--
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-- the conversion is only equivalent if the GFC grammar has a context-free backbone.
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-----------------------------------------------------------------------------
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module GF.Conversion.SimpleToFCFG
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(convertGrammar) where
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import GF.System.Tracing
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import GF.Infra.Print
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import GF.Infra.Ident
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import Control.Monad
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import GF.Formalism.Utilities
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import GF.Formalism.FCFG
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import GF.Conversion.Types
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import GF.Canon.GFCC.AbsGFCC
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import GF.Canon.GFCC.DataGFCC
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import GF.Data.BacktrackM
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import GF.Data.SortedList
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import GF.Data.Utilities (updateNthM)
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import qualified Data.Map as Map
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import qualified Data.Set as Set
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import qualified Data.List as List
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import Data.Array
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import Data.Maybe
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----------------------------------------------------------------------
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-- main conversion function
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convertGrammar :: Grammar -> [(Ident,FGrammar)]
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convertGrammar g@(Grm hdr (Abs abs_defs) cncs) = [(i2i cncname,convert abs_defs conc) | cncname <- cncnames gfcc, conc <- Map.lookup cncname (concretes gfcc)]
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where
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gfcc = mkGFCC g
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i2i (CId i) = IC i
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convert :: [AbsDef] -> TermMap -> FGrammar
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convert abs_defs cnc_defs = getFRules (loop frulesEnv)
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where
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srules = [(XRule id args res (map findLinType args) (findLinType res) term) | Fun id (Typ args res) exp <- abs_defs, term <- Map.lookup id cnc_defs]
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findLinType (CId id) = fromJust (Map.lookup (CId ("__"++id)) cnc_defs)
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(srulesMap,frulesEnv) = List.foldl' helper (Map.empty,emptyFRulesEnv) srules
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where
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helper (srulesMap,frulesEnv) rule@(XRule id abs_args abs_res cnc_args cnc_res term) =
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let srulesMap' = Map.insertWith (++) abs_res [rule] srulesMap
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frulesEnv' = List.foldl' (\env selector -> convertRule cnc_defs selector rule env)
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frulesEnv
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(mkSingletonSelectors cnc_res)
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in srulesMap' `seq` frulesEnv' `seq` (srulesMap',frulesEnv')
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loop frulesEnv =
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let (todo, frulesEnv') = takeToDoRules srulesMap frulesEnv
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in case todo of
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[] -> frulesEnv'
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_ -> loop $! List.foldl' (\env (srules,selector) ->
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List.foldl' (\env srule -> convertRule cnc_defs selector srule env) env srules) frulesEnv' todo
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convertRule :: TermMap -> TermSelector -> XRule -> FRulesEnv -> FRulesEnv
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convertRule cnc_defs selector (XRule fun args cat ctypes ctype term) frulesEnv =
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foldBM addRule
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frulesEnv
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(convertTerm cnc_defs selector term [([],[])])
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(initialFCat cat, map (\scat -> (initialFCat scat,[])) args, ctype, ctypes)
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where
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addRule linRec (newCat', newArgs', _, _) env0 =
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let (env1, newCat) = genFCatHead env0 newCat'
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(env2, newArgs,idxArgs) = foldr (\((fcat@(FCat _ cat rcs tcs),xpaths),ctype,idx) (env,args,all_args) ->
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let xargs = fcat:[FCat 0 cat [path] tcs | path <- reverse xpaths]
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(env1, xargs1) = List.mapAccumL (genFCatArg ctype) env xargs
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in case fcat of
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FCat _ _ [] _ -> (env , args, all_args)
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_ -> (env1,xargs1++args,(idx,xargs1):all_args)) (env1,[],[]) (zip3 newArgs' ctypes [0..])
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newLinRec = listArray (0,length linRec-1) [translateLin idxArgs path linRec | path <- case newCat of {FCat _ _ rcs _ -> rcs}]
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(_,newProfile) = List.mapAccumL accumProf 0 newArgs'
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where
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accumProf nr (FCat _ _ [] _,_ ) = (nr, Unify [] )
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accumProf nr (_ ,xpaths) = (nr+cnt+1, Unify [nr..nr+cnt])
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where cnt = length xpaths
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rule = FRule (Name fun newProfile) newArgs newCat newLinRec
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in addFCatRule env2 rule
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translateLin idxArgs lbl' [] = array (0,-1) []
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translateLin idxArgs lbl' ((lbl,syms) : lins)
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| lbl' == lbl = listArray (0,length syms-1) (map instSym syms)
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| otherwise = translateLin idxArgs lbl' lins
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where
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instSym = symbol (\(lbl, nr, xnr) -> instCat lbl nr xnr 0 idxArgs) FSymTok
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instCat lbl nr xnr nr' ((idx,xargs):idxArgs)
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| nr == idx = let arg@(FCat _ _ rcs _) = xargs !! xnr
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in FSymCat arg (index lbl rcs 0) (nr'+xnr)
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| otherwise = instCat lbl nr xnr (nr'+length xargs) idxArgs
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index lbl' (lbl:lbls) idx
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| lbl' == lbl = idx
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| otherwise = index lbl' lbls $! (idx+1)
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----------------------------------------------------------------------
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-- term conversion
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type CnvMonad a = BacktrackM Env a
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type Env = (FCat, [(FCat,[FPath])], Term, [Term])
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type LinRec = [(FPath, [Symbol (FPath, FIndex, Int) Token])]
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type TermMap = Map.Map CId Term
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convertTerm :: TermMap -> TermSelector -> Term -> LinRec -> CnvMonad LinRec
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convertTerm cnc_defs selector (V nr) ((lbl_path,lin) : lins) = convertArg selector nr [] lbl_path lin lins
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convertTerm cnc_defs selector (C nr) ((lbl_path,lin) : lins) = convertCon selector nr lbl_path lin lins
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convertTerm cnc_defs selector (R record) ((lbl_path,lin) : lins) = convertRec cnc_defs selector 0 record lbl_path lin lins
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convertTerm cnc_defs selector (P term sel) lins = do nr <- evalTerm cnc_defs [] sel
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convertTerm cnc_defs (TuplePrj nr selector) term lins
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convertTerm cnc_defs selector (FV vars) lins = do term <- member vars
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convertTerm cnc_defs selector term lins
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convertTerm cnc_defs selector (S ts) ((lbl_path,lin) : lins) = do projectHead lbl_path
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foldM (\lins t -> convertTerm cnc_defs selector t lins) ((lbl_path,lin) : lins) (reverse ts)
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convertTerm cnc_defs selector (KS str) ((lbl_path,lin) : lins) = do projectHead lbl_path
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return ((lbl_path,Tok str : lin) : lins)
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convertTerm cnc_defs selector (KP (str:_)_)((lbl_path,lin) : lins) = do projectHead lbl_path
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return ((lbl_path,Tok str : lin) : lins)
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convertTerm cnc_defs selector (RP _ term) lins = convertTerm cnc_defs selector term lins
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convertTerm cnc_defs selector (F id) lins = do term <- Map.lookup id cnc_defs
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convertTerm cnc_defs selector term lins
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convertTerm cnc_defs selector (W s ss) ((lbl_path,lin) : lins) = convertRec cnc_defs selector 0 [KS (s ++ s1) | s1 <- ss] lbl_path lin lins
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convertTerm cnc_defs selector x lins = error ("convertTerm ("++show x++")")
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convertArg (TupleSel record) nr path lbl_path lin lins =
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foldM (\lins (lbl, selector) -> convertArg selector nr (lbl:path) (lbl:lbl_path) lin lins) lins record
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convertArg (TuplePrj lbl selector) nr path lbl_path lin lins =
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convertArg selector nr (lbl:path) lbl_path lin lins
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convertArg (ConSel indices) nr path lbl_path lin lins = do
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index <- member indices
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restrictHead lbl_path index
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restrictArg nr path index
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return lins
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convertArg StrSel nr path lbl_path lin lins = do
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projectHead lbl_path
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xnr <- projectArg nr path
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return ((lbl_path, Cat (path, nr, xnr) : lin) : lins)
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convertCon (ConSel indices) index lbl_path lin lins = do
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guard (index `elem` indices)
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restrictHead lbl_path index
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return lins
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convertRec cnc_defs selector index [] lbl_path lin lins = return lins
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convertRec cnc_defs selector@(TupleSel fields) index (val:record) lbl_path lin lins = select fields
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where
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select [] = convertRec cnc_defs selector (index+1) record lbl_path lin lins
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select ((index',sub_sel) : fields)
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| index == index' = do lins <- convertTerm cnc_defs sub_sel val ((index:lbl_path,lin) : lins)
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convertRec cnc_defs selector (index+1) record lbl_path lin lins
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| otherwise = select fields
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convertRec cnc_defs (TuplePrj index' sub_sel) index record lbl_path lin lins = do
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convertTerm cnc_defs sub_sel (record !! (index'-index)) ((lbl_path,lin) : lins)
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------------------------------------------------------------
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-- eval a term to ground terms
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evalTerm :: TermMap -> FPath -> Term -> CnvMonad FIndex
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evalTerm cnc_defs path (V nr) = do term <- readArgCType nr
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unifyPType nr (reverse path) (selectTerm path term)
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evalTerm cnc_defs path (C nr) = return nr
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evalTerm cnc_defs path (R record) = case path of
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(index:path) -> evalTerm cnc_defs path (record !! index)
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evalTerm cnc_defs path (P term sel) = do index <- evalTerm cnc_defs [] sel
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evalTerm cnc_defs (index:path) term
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evalTerm cnc_defs path (FV terms) = member terms >>= evalTerm cnc_defs path
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evalTerm cnc_defs path (RP alias _) = evalTerm cnc_defs path alias
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evalTerm cnc_defs path (F id) = do term <- Map.lookup id cnc_defs
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evalTerm cnc_defs path term
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evalTerm cnc_defs path x = error ("evalTerm ("++show x++")")
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unifyPType :: FIndex -> FPath -> Term -> CnvMonad FIndex
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unifyPType nr path (C max_index) =
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do (_, args, _, _) <- readState
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let (FCat _ _ _ tcs,_) = args !! nr
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case lookup path tcs of
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Just index -> return index
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Nothing -> do index <- member [0..max_index-1]
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restrictArg nr path index
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return index
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unifyPType nr path (RP alias _) = unifyPType nr path alias
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selectTerm :: FPath -> Term -> Term
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selectTerm [] term = term
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selectTerm (index:path) (R record) = selectTerm path (record !! index)
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selectTerm path (RP _ term) = selectTerm path term
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----------------------------------------------------------------------
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-- FRulesEnv
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data FRulesEnv = FRulesEnv {-# UNPACK #-} !Int FCatSet [FRule]
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type XRulesMap = Map.Map CId [XRule]
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data XRule = XRule CId {- function -}
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[CId] {- argument types -}
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CId {- result type -}
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[Term] {- argument lin-types representation -}
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Term {- result lin-type representation -}
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Term {- body -}
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type FCatSet = Map.Map CId (Map.Map [FPath] (Map.Map [(FPath,FIndex)] (Either FCat FCat)))
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emptyFRulesEnv = FRulesEnv 0 (ins fcatString (ins fcatInt (ins fcatFloat Map.empty))) []
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where
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ins fcat@(FCat _ cat rcs tcs) fcatSet =
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Map.insertWith (\_ -> Map.insertWith (\_ -> Map.insert tcs x_fcat) rcs tmap_s) cat rmap_s fcatSet
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where
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x_fcat = Right fcat
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tmap_s = Map.singleton tcs x_fcat
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rmap_s = Map.singleton rcs tmap_s
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genFCatHead :: FRulesEnv -> FCat -> (FRulesEnv, FCat)
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genFCatHead env@(FRulesEnv last_id fcatSet rules) m1@(FCat _ cat rcs tcs) =
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case Map.lookup cat fcatSet >>= Map.lookup rcs >>= Map.lookup tcs of
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Just (Left fcat) -> (FRulesEnv last_id (ins fcat) rules, fcat)
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Just (Right fcat) -> (env, fcat)
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Nothing -> let next_id = last_id+1
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fcat = FCat next_id cat rcs tcs
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in (FRulesEnv next_id (ins fcat) rules, fcat)
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where
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ins fcat = Map.insertWith (\_ -> Map.insertWith (\_ -> Map.insert tcs x_fcat) rcs tmap_s) cat rmap_s fcatSet
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where
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x_fcat = Right fcat
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tmap_s = Map.singleton tcs x_fcat
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rmap_s = Map.singleton rcs tmap_s
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genFCatArg :: Term -> FRulesEnv -> FCat -> (FRulesEnv, FCat)
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genFCatArg ctype env@(FRulesEnv last_id fcatSet rules) m1@(FCat _ cat rcs tcs) =
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case Map.lookup cat fcatSet >>= Map.lookup rcs of
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Just tmap -> case Map.lookup tcs tmap of
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Just (Left fcat) -> (env, fcat)
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Just (Right fcat) -> (env, fcat)
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Nothing -> ins tmap
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Nothing -> ins Map.empty
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where
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ins tmap =
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let next_id = last_id+1
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fcat = FCat next_id cat rcs tcs
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(x_fcat,last_id1,tmap1,rules1)
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= foldBM (\tcs st (x_fcat,last_id,tmap,rules) ->
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let (last_id1,tmap1,fcat_arg) = addArg tcs last_id tmap
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rule = FRule (Name (CId "_") [Unify [0]]) [fcat_arg] fcat
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(listArray (0,length rcs-1) [listArray (0,0) [FSymCat fcat_arg lbl 0] | lbl <- [0..length rcs-1]])
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in if st
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then (Right fcat,last_id1,tmap1,rule:rules)
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else (x_fcat, last_id, tmap, rules))
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(Left fcat,next_id,Map.insert tcs x_fcat tmap,rules)
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(gen_tcs ctype [] [])
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False
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rmap1 = Map.singleton rcs tmap1
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in (FRulesEnv last_id1 (Map.insertWith (\_ -> Map.insert rcs tmap1) cat rmap1 fcatSet) rules1, fcat)
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where
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addArg tcs last_id tmap =
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case Map.lookup tcs tmap of
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Just (Left fcat) -> (last_id, tmap, fcat)
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Just (Right fcat) -> (last_id, tmap, fcat)
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Nothing -> let next_id = last_id+1
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fcat = FCat next_id cat rcs tcs
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in (next_id, Map.insert tcs (Left fcat) tmap, fcat)
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gen_tcs :: Term -> FPath -> [(FPath,FIndex)] -> BacktrackM Bool [(FPath,FIndex)]
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gen_tcs (R record) path acc = foldM (\acc (label,ctype) -> gen_tcs ctype (label:path) acc) acc (zip [0..] record)
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gen_tcs (S _) path acc = return acc
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gen_tcs (RP _ term) path acc = gen_tcs term path acc
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gen_tcs (C max_index) path acc =
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case List.lookup path tcs of
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Just index -> return $! addConstraint path index acc
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Nothing -> do writeState True
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index <- member [0..max_index-1]
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return $! addConstraint path index acc
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where
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addConstraint path0 index0 (c@(path,index) : cs)
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| path0 > path = c:addConstraint path0 index0 cs
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addConstraint path0 index0 cs = (path0,index0) : cs
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takeToDoRules :: XRulesMap -> FRulesEnv -> ([([XRule], TermSelector)], FRulesEnv)
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takeToDoRules srulesMap (FRulesEnv last_id fcatSet rules) = (todo,FRulesEnv last_id fcatSet' rules)
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where
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(todo,fcatSet') =
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Map.mapAccumWithKey (\todo cat rmap ->
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let (todo1,rmap1) = Map.mapAccumWithKey (\todo rcs tmap ->
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let (tcss,tmap') = Map.mapAccumWithKey (\tcss tcs x_fcat ->
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case x_fcat of
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Left fcat -> (tcs:tcss,Right fcat)
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Right fcat -> ( tcss, x_fcat)) [] tmap
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in case tcss of
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[] -> ( todo,tmap )
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_ -> ((srules,mkSelector rcs tcss) : todo,tmap')) todo rmap
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mb_srules = Map.lookup cat srulesMap
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Just srules = mb_srules
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in case mb_srules of
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Just srules -> (todo1,rmap1)
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Nothing -> (todo ,rmap1)) [] fcatSet
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addFCatRule :: FRulesEnv -> FRule -> FRulesEnv
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addFCatRule (FRulesEnv last_id fcatSet rules) rule = FRulesEnv last_id fcatSet (rule:rules)
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getFRules :: FRulesEnv -> [FRule]
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getFRules (FRulesEnv last_id fcatSet rules) = rules
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------------------------------------------------------------
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-- The TermSelector
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data TermSelector
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= TupleSel [(FIndex, TermSelector)]
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| TuplePrj FIndex TermSelector
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| ConSel [FIndex]
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| StrSel
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deriving Show
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mkSingletonSelectors :: Term -- ^ Type representation term
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-> [TermSelector] -- ^ list of selectors containing just one string field
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mkSingletonSelectors term = sels0
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where
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(sels0,tcss0) = loop [] ([],[]) term
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loop path st (R record) = List.foldl' (\st (index,term) -> loop (index:path) st term) st (zip [0..] record)
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loop path st (RP _ t) = loop path st t
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loop path (sels,tcss) (C i) = ( sels,map ((,) path) [0..i-1] : tcss)
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loop path (sels,tcss) (S _) = (mkSelector [path] tcss0 : sels, tcss)
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mkSelector :: [FPath] -> [[(FPath,FIndex)]] -> TermSelector
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mkSelector rcs tcss =
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List.foldl' addRestriction (case xs of
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(path:xs) -> List.foldl' addProjection (path2selector StrSel path) xs) ys
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where
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xs = [ reverse path | path <- rcs]
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ys = [(reverse path,term) | tcs <- tcss, (path,term) <- tcs]
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addRestriction :: TermSelector -> (FPath,FIndex) -> TermSelector
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addRestriction (ConSel indices) ([] ,n_index) = ConSel (add indices)
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where
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add [] = [n_index]
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add (index':indices)
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| n_index == index' = index': indices
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| otherwise = index':add indices
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addRestriction (TupleSel fields) (index : path,n_index) = TupleSel (add fields)
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where
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add [] = [(index,path2selector (ConSel [n_index]) path)]
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add (field@(index',sub_sel):fields)
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| index == index' = (index',addRestriction sub_sel (path,n_index)):fields
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| otherwise = field : add fields
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addProjection :: TermSelector -> FPath -> TermSelector
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addProjection StrSel [] = StrSel
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addProjection (TupleSel fields) (index : path) = TupleSel (add fields)
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where
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add [] = [(index,path2selector StrSel path)]
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add (field@(index',sub_sel):fields)
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| index == index' = (index',addProjection sub_sel path):fields
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| otherwise = field : add fields
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path2selector base [] = base
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path2selector base (index : path) = TupleSel [(index,path2selector base path)]
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------------------------------------------------------------
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-- updating the MCF rule
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readArgCType :: FIndex -> CnvMonad Term
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readArgCType nr = do (_, _, _, ctypes) <- readState
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return (ctypes !! nr)
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restrictArg :: FIndex -> FPath -> FIndex -> CnvMonad ()
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restrictArg nr path index = do
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(head, args, ctype, ctypes) <- readState
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args' <- updateNthM (\(fcat,xs) -> do fcat <- restrictFCat path index fcat
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return (fcat,xs) ) nr args
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writeState (head, args', ctype, ctypes)
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projectArg :: FIndex -> FPath -> CnvMonad Int
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projectArg nr path = do
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(head, args, ctype, ctypes) <- readState
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(xnr,args') <- updateArgs nr args
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|
writeState (head, args', ctype, ctypes)
|
|
return xnr
|
|
where
|
|
updateArgs :: FIndex -> [(FCat,[FPath])] -> CnvMonad (Int,[(FCat,[FPath])])
|
|
updateArgs 0 ((a@(FCat _ _ rcs _),xpaths) : as)
|
|
| path `elem` rcs = return (length xpaths+1,(a,path:xpaths):as)
|
|
| otherwise = do a <- projectFCat path a
|
|
return (0,(a,xpaths):as)
|
|
updateArgs n (a : as) = do
|
|
(xnr,as) <- updateArgs (n-1) as
|
|
return (xnr,a:as)
|
|
|
|
readHeadCType :: CnvMonad Term
|
|
readHeadCType = do (_, _, ctype, _) <- readState
|
|
return ctype
|
|
|
|
restrictHead :: FPath -> FIndex -> CnvMonad ()
|
|
restrictHead path term
|
|
= do (head, args, ctype, ctypes) <- readState
|
|
head' <- restrictFCat path term head
|
|
writeState (head', args, ctype, ctypes)
|
|
|
|
projectHead :: FPath -> CnvMonad ()
|
|
projectHead path
|
|
= do (head, args, ctype, ctypes) <- readState
|
|
head' <- projectFCat path head
|
|
writeState (head', args, ctype, ctypes)
|
|
|
|
restrictFCat :: FPath -> FIndex -> FCat -> CnvMonad FCat
|
|
restrictFCat path0 index0 (FCat id cat rcs tcs) = do
|
|
tcs <- addConstraint tcs
|
|
return (FCat id cat rcs tcs)
|
|
where
|
|
addConstraint (c@(path,index) : cs)
|
|
| path0 > path = liftM (c:) (addConstraint cs)
|
|
| path0 == path = guard (index0 == index) >>
|
|
return (c : cs)
|
|
addConstraint cs = return ((path0,index0) : cs)
|
|
|
|
projectFCat :: FPath -> FCat -> CnvMonad FCat
|
|
projectFCat path0 (FCat id cat rcs tcs) = do
|
|
return (FCat id cat (addConstraint rcs) tcs)
|
|
where
|
|
addConstraint (path : rcs)
|
|
| path0 > path = path : addConstraint rcs
|
|
| path0 == path = path : rcs
|
|
addConstraint rcs = path0 : rcs
|