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CFGtoPGF is now extended to support context-free grammars with primitive parameters

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This commit is contained in:
krasimir
2016-03-22 10:28:15 +00:00
parent fbdf21d862
commit ce70720859
9 changed files with 192 additions and 166 deletions
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40
src/compiler/GF/Grammar/BNFC.hs
View File

@@ -16,7 +16,7 @@ module GF.Grammar.BNFC(BNFCRule(..), BNFCSymbol, Symbol(..), CFTerm(..), bnfc2cf
import GF.Grammar.CFG
import PGF (Token, mkCId)
import Data.List (lookup, partition)
import Data.List (partition)
type IsList = Bool
type BNFCSymbol = Symbol (Cat, IsList) Token
@@ -42,7 +42,7 @@ type IsSeparator = Bool
type SepTermSymb = String
type SepMap = [(Cat, (IsNonempty, IsSeparator, SepTermSymb))]
bnfc2cf :: [BNFCRule] -> [CFRule]
bnfc2cf :: [BNFCRule] -> [ParamCFRule]
bnfc2cf rules = concatMap (transformRules (map makeSepTerm rules1)) rules2
where (rules1,rules2) = partition isSepTerm rules
makeSepTerm (BNFCTerminator ne c s) = (c, (ne, False, s))
@@ -53,46 +53,46 @@ isSepTerm (BNFCTerminator {}) = True
isSepTerm (BNFCSeparator {}) = True
isSepTerm _ = False
transformRules :: SepMap -> BNFCRule -> [CFRule]
transformRules sepMap (BNFCRule c smbs@(s:ss) r) = CFRule c cfSmbs r : rls
transformRules :: SepMap -> BNFCRule -> [ParamCFRule]
transformRules sepMap (BNFCRule c smbs@(s:ss) r) = Rule (c,[0]) cfSmbs r : rls
where smbs' = map transformSymb smbs
cfSmbs = [snd s | s <- smbs']
ids = filter (/= "") [fst s | s <- smbs']
rls = concatMap (createListRules sepMap) ids
transformRules sepMap (BNFCCoercions c num) = rules ++ [lastRule]
where rules = map (fRules c) [0..num-1]
lastRule = CFRule c' ss rn
lastRule = Rule (c',[0]) ss rn
where c' = c ++ show num
ss = [Terminal "(", NonTerminal c, Terminal ")"]
ss = [Terminal "(", NonTerminal (c,[0]), Terminal ")"]
rn = CFObj (mkCId $ "coercion_" ++ c) []
fRules c n = CFRule c' ss rn
fRules c n = Rule (c',[0]) ss rn
where c' = if n == 0 then c else c ++ show n
ss = [NonTerminal (c ++ show (n+1))]
rn = CFObj (mkCId $ "coercion_" ++ c')[]
ss = [NonTerminal (c ++ show (n+1),[0])]
rn = CFObj (mkCId $ "coercion_" ++ c') []
transformSymb :: BNFCSymbol -> (String, CFSymbol)
transformSymb :: BNFCSymbol -> (String, ParamCFSymbol)
transformSymb s = case s of
NonTerminal (c,False) -> ("", NonTerminal c)
NonTerminal (c,True ) -> (c , NonTerminal $ "List" ++ c)
NonTerminal (c,False) -> ("", NonTerminal (c,[0]))
NonTerminal (c,True ) -> (c , NonTerminal $ ("List" ++ c,[0]))
Terminal t -> ("", Terminal t)
createListRules :: SepMap -> String -> [CFRule]
createListRules :: SepMap -> String -> [ParamCFRule]
createListRules sepMap c =
case lookup c sepMap of
Just (ne, isSep, symb) -> createListRules' ne isSep symb c
Nothing -> createListRules' False True "" c
createListRules':: IsNonempty -> IsSeparator -> SepTermSymb -> String -> [CFRule]
createListRules':: IsNonempty -> IsSeparator -> SepTermSymb -> String -> [ParamCFRule]
createListRules' ne isSep symb c = ruleCons : [ruleBase]
where ruleBase = CFRule ("List" ++ c) smbs rn
where ruleBase = Rule ("List" ++ c,[0]) smbs rn
where smbs = if isSep
then [NonTerminal c | ne]
else [NonTerminal c | ne] ++
then [NonTerminal (c,[0]) | ne]
else [NonTerminal (c,[0]) | ne] ++
[Terminal symb | symb /= "" && ne]
rn = CFObj (mkCId $ "Base" ++ c) []
ruleCons = CFRule ("List" ++ c) smbs rn
where smbs = [NonTerminal c] ++
ruleCons = Rule ("List" ++ c,[0]) smbs rn
where smbs = [NonTerminal (c,[0])] ++
[Terminal symb | symb /= ""] ++
[NonTerminal ("List" ++ c)]
[NonTerminal ("List" ++ c,[0])]
rn = CFObj (mkCId $ "Cons" ++ c) []

170
src/compiler/GF/Grammar/CFG.hs
View File

@@ -8,16 +8,11 @@ module GF.Grammar.CFG where
import GF.Data.Utilities
import PGF
--import GF.Infra.Option
import GF.Data.Relation
--import Control.Monad
--import Control.Monad.State (State, get, put, evalState)
import Data.Map (Map)
import qualified Data.Map as Map
import Data.List
--import Data.Maybe (fromMaybe)
--import Data.Monoid (mconcat)
import Data.Set (Set)
import qualified Data.Set as Set
@@ -30,15 +25,19 @@ type Cat = String
data Symbol c t = NonTerminal c | Terminal t
deriving (Eq, Ord, Show)
type CFSymbol = Symbol Cat Token
data CFRule = CFRule {
lhsCat :: Cat,
ruleRhs :: [CFSymbol],
data Rule c t = Rule {
ruleLhs :: c,
ruleRhs :: [Symbol c t],
ruleName :: CFTerm
}
deriving (Eq, Ord, Show)
data Grammar c t = Grammar {
cfgStartCat :: c,
cfgExternalCats :: Set c,
cfgRules :: Map c (Set (Rule c t)) }
deriving (Eq, Ord, Show)
data CFTerm
= CFObj CId [CFTerm] -- ^ an abstract syntax function with arguments
| CFAbs Int CFTerm -- ^ A lambda abstraction. The Int is the variable id.
@@ -48,11 +47,14 @@ data CFTerm
| CFMeta CId -- ^ A metavariable
deriving (Eq, Ord, Show)
data CFG = CFG { cfgStartCat :: Cat,
cfgExternalCats :: Set Cat,
cfgRules :: Map Cat (Set CFRule) }
deriving (Eq, Ord, Show)
type CFSymbol = Symbol Cat Token
type CFRule = Rule Cat Token
type CFG = Grammar Cat Token
type Param = Int
type ParamCFSymbol = Symbol (Cat,[Param]) Token
type ParamCFRule = Rule (Cat,[Param]) Token
type ParamCFG = Grammar (Cat,[Param]) Token
--
-- * Grammar filtering
@@ -64,25 +66,25 @@ data CFG = CFG { cfgStartCat :: Cat,
-- one should we pick?
-- FIXME: Does not (yet) remove productions which are cyclic
-- because of empty productions.
removeCycles :: CFG -> CFG
removeCycles :: (Ord c,Ord t) => Grammar c t -> Grammar c t
removeCycles = onRules f
where f rs = filter (not . isCycle) rs
where alias = transitiveClosure $ mkRel [(c,c') | CFRule c [NonTerminal c'] _ <- rs]
isCycle (CFRule c [NonTerminal c'] _) = isRelatedTo alias c' c
where alias = transitiveClosure $ mkRel [(c,c') | Rule c [NonTerminal c'] _ <- rs]
isCycle (Rule c [NonTerminal c'] _) = isRelatedTo alias c' c
isCycle _ = False
-- | Better bottom-up filter that also removes categories which contain no finite
-- strings.
bottomUpFilter :: CFG -> CFG
bottomUpFilter :: (Ord c,Ord t) => Grammar c t -> Grammar c t
bottomUpFilter gr = fix grow (gr { cfgRules = Map.empty })
where grow g = g `unionCFG` filterCFG (all (okSym g) . ruleRhs) gr
okSym g = symbol (`elem` allCats g) (const True)
-- | Removes categories which are not reachable from any external category.
topDownFilter :: CFG -> CFG
topDownFilter :: (Ord c,Ord t) => Grammar c t -> Grammar c t
topDownFilter cfg = filterCFGCats (`Set.member` keep) cfg
where
rhsCats = [ (lhsCat r, c') | r <- allRules cfg, c' <- filterCats (ruleRhs r) ]
rhsCats = [ (ruleLhs r, c') | r <- allRules cfg, c' <- filterCats (ruleRhs r) ]
uses = reflexiveClosure_ (allCats cfg) $ transitiveClosure $ mkRel rhsCats
keep = Set.unions $ map (allRelated uses) $ Set.toList $ cfgExternalCats cfg
@@ -95,12 +97,12 @@ mergeIdentical g = onRules (map subst) g
m = Map.fromList [(y,concat (intersperse "+" xs))
| (_,xs) <- buildMultiMap [(rulesKey rs,c) | (c,rs) <- Map.toList (cfgRules g)], y <- xs]
-- build data to compare for each category: a set of name,rhs pairs
rulesKey = Set.map (\ (CFRule _ r n) -> (n,r))
subst (CFRule c r n) = CFRule (substCat c) (map (mapSymbol substCat id) r) n
rulesKey = Set.map (\ (Rule _ r n) -> (n,r))
subst (Rule c r n) = Rule (substCat c) (map (mapSymbol substCat id) r) n
substCat c = Map.findWithDefault (error $ "mergeIdentical: " ++ c) c m
-- | Keeps only the start category as an external category.
purgeExternalCats :: CFG -> CFG
purgeExternalCats :: Grammar c t -> Grammar c t
purgeExternalCats cfg = cfg { cfgExternalCats = Set.singleton (cfgStartCat cfg) }
--
@@ -113,7 +115,7 @@ removeLeftRecursion :: CFG -> CFG
removeLeftRecursion gr
= gr { cfgRules = groupProds $ concat [scheme1, scheme2, scheme3, scheme4] }
where
scheme1 = [CFRule a [x,NonTerminal a_x] n' |
scheme1 = [Rule a [x,NonTerminal a_x] n' |
a <- retainedLeftRecursive,
x <- properLeftCornersOf a,
not (isLeftRecursive x),
@@ -123,27 +125,27 @@ removeLeftRecursion gr
a_x `Set.member` newCats,
let n' = symbol (\_ -> CFApp (CFRes 1) (CFRes 0))
(\_ -> CFRes 0) x]
scheme2 = [CFRule a_x (beta++[NonTerminal a_b]) n' |
scheme2 = [Rule a_x (beta++[NonTerminal a_b]) n' |
a <- retainedLeftRecursive,
b@(NonTerminal b') <- properLeftCornersOf a,
isLeftRecursive b,
CFRule _ (x:beta) n <- catRules gr b',
Rule _ (x:beta) n <- catRules gr b',
let a_x = mkCat (NonTerminal a) x,
let a_b = mkCat (NonTerminal a) b,
let i = length $ filterCats beta,
let n' = symbol (\_ -> CFAbs 1 (CFApp (CFRes i) (shiftTerm n)))
(\_ -> CFApp (CFRes i) n) x]
scheme3 = [CFRule a_x beta n' |
scheme3 = [Rule a_x beta n' |
a <- retainedLeftRecursive,
x <- properLeftCornersOf a,
CFRule _ (x':beta) n <- catRules gr a,
Rule _ (x':beta) n <- catRules gr a,
x == x',
let a_x = mkCat (NonTerminal a) x,
let n' = symbol (\_ -> CFAbs 1 (shiftTerm n))
(\_ -> n) x]
scheme4 = catSetRules gr $ Set.fromList $ filter (not . isLeftRecursive . NonTerminal) cats
newCats = Set.fromList (map lhsCat (scheme2 ++ scheme3))
newCats = Set.fromList (map ruleLhs (scheme2 ++ scheme3))
shiftTerm :: CFTerm -> CFTerm
shiftTerm (CFObj f ts) = CFObj f (map shiftTerm ts)
@@ -155,7 +157,7 @@ removeLeftRecursion gr
cats = allCats gr
-- rules = allRules gr
directLeftCorner = mkRel [(NonTerminal c,t) | CFRule c (t:_) _ <- allRules gr]
directLeftCorner = mkRel [(NonTerminal c,t) | Rule c (t:_) _ <- allRules gr]
-- leftCorner = reflexiveClosure_ (map NonTerminal cats) $ transitiveClosure directLeftCorner
properLeftCorner = transitiveClosure directLeftCorner
properLeftCornersOf = Set.toList . allRelated properLeftCorner . NonTerminal
@@ -176,11 +178,12 @@ removeLeftRecursion gr
where showSymbol = symbol id show
-- | Get the sets of mutually recursive non-terminals for a grammar.
mutRecCats :: Bool -- ^ If true, all categories will be in some set.
mutRecCats :: Ord c
=> Bool -- ^ If true, all categories will be in some set.
-- If false, only recursive categories will be included.
-> CFG -> [Set Cat]
-> Grammar c t -> [Set c]
mutRecCats incAll g = equivalenceClasses $ refl $ symmetricSubrelation $ transitiveClosure r
where r = mkRel [(c,c') | CFRule c ss _ <- allRules g, NonTerminal c' <- ss]
where r = mkRel [(c,c') | Rule c ss _ <- allRules g, NonTerminal c' <- ss]
refl = if incAll then reflexiveClosure_ (allCats g) else reflexiveSubrelation
--
@@ -199,107 +202,108 @@ makeRegular g = g { cfgRules = groupProds $ concatMap trSet (mutRecCats True g)
where trSet cs | allXLinear cs rs = rs
| otherwise = concatMap handleCat (Set.toList cs)
where rs = catSetRules g cs
handleCat c = [CFRule c' [] (mkCFTerm (c++"-empty"))] -- introduce A' -> e
handleCat c = [Rule c' [] (mkCFTerm (c++"-empty"))] -- introduce A' -> e
++ concatMap (makeRightLinearRules c) (catRules g c)
where c' = newCat c
makeRightLinearRules b' (CFRule c ss n) =
makeRightLinearRules b' (Rule c ss n) =
case ys of
[] -> newRule b' (xs ++ [NonTerminal (newCat c)]) n -- no non-terminals left
(NonTerminal b:zs) -> newRule b' (xs ++ [NonTerminal b]) n
++ makeRightLinearRules (newCat b) (CFRule c zs n)
++ makeRightLinearRules (newCat b) (Rule c zs n)
where (xs,ys) = break (`catElem` cs) ss
-- don't add rules on the form A -> A
newRule c rhs n | rhs == [NonTerminal c] = []
| otherwise = [CFRule c rhs n]
| otherwise = [Rule c rhs n]
newCat c = c ++ "$"
--
-- * CFG Utilities
--
mkCFG :: Cat -> Set Cat -> [CFRule] -> CFG
mkCFG start ext rs = CFG { cfgStartCat = start, cfgExternalCats = ext, cfgRules = groupProds rs }
mkCFG :: (Ord c,Ord t) => c -> Set c -> [Rule c t] -> Grammar c t
mkCFG start ext rs = Grammar { cfgStartCat = start, cfgExternalCats = ext, cfgRules = groupProds rs }
groupProds :: [CFRule] -> Map Cat (Set CFRule)
groupProds = Map.fromListWith Set.union . map (\r -> (lhsCat r,Set.singleton r))
groupProds :: (Ord c,Ord t) => [Rule c t] -> Map c (Set (Rule c t))
groupProds = Map.fromListWith Set.union . map (\r -> (ruleLhs r,Set.singleton r))
uniqueFuns :: CFG -> CFG
uniqueFuns cfg = CFG {cfgStartCat = cfgStartCat cfg
,cfgExternalCats = cfgExternalCats cfg
,cfgRules = Map.fromList (snd (mapAccumL uniqueFunSet Set.empty (Map.toList (cfgRules cfg))))
}
uniqueFuns :: (Ord c,Ord t) => Grammar c t -> Grammar c t
uniqueFuns cfg = Grammar {cfgStartCat = cfgStartCat cfg
,cfgExternalCats = cfgExternalCats cfg
,cfgRules = Map.fromList (snd (mapAccumL uniqueFunSet Set.empty (Map.toList (cfgRules cfg))))
}
where
uniqueFunSet funs (cat,rules) =
let (funs',rules') = mapAccumL uniqueFun funs (Set.toList rules)
in (funs',(cat,Set.fromList rules'))
uniqueFun funs (CFRule cat items (CFObj fun args)) = (Set.insert fun' funs,CFRule cat items (CFObj fun' args))
uniqueFun funs (Rule cat items (CFObj fun args)) = (Set.insert fun' funs,Rule cat items (CFObj fun' args))
where
fun' = head [fun'|suffix<-"":map show ([2..]::[Int]),
let fun'=mkCId (showCId fun++suffix),
not (fun' `Set.member` funs)]
-- | Gets all rules in a CFG.
allRules :: CFG -> [CFRule]
allRules = concat . map Set.toList . Map.elems . cfgRules
allRules :: Grammar c t -> [Rule c t]
allRules = concatMap Set.toList . Map.elems . cfgRules
-- | Gets all rules in a CFG, grouped by their LHS categories.
allRulesGrouped :: CFG -> [(Cat,[CFRule])]
allRulesGrouped :: Grammar c t -> [(c,[Rule c t])]
allRulesGrouped = Map.toList . Map.map Set.toList . cfgRules
-- | Gets all categories which have rules.
allCats :: CFG -> [Cat]
allCats :: Grammar c t -> [c]
allCats = Map.keys . cfgRules
-- | Gets all categories which have rules or occur in a RHS.
allCats' :: CFG -> [Cat]
allCats' :: (Ord c,Ord t) => Grammar c t -> [c]
allCats' cfg = Set.toList (Map.keysSet (cfgRules cfg) `Set.union`
Set.fromList [c | rs <- Map.elems (cfgRules cfg),
r <- Set.toList rs,
NonTerminal c <- ruleRhs r])
-- | Gets all rules for the given category.
catRules :: CFG -> Cat -> [CFRule]
catRules :: Ord c => Grammar c t -> c -> [Rule c t]
catRules gr c = Set.toList $ Map.findWithDefault Set.empty c (cfgRules gr)
-- | Gets all rules for categories in the given set.
catSetRules :: CFG -> Set Cat -> [CFRule]
catSetRules gr cs = allRules $ filterCFGCats (`Set.member` cs) gr
mapCFGCats :: (Cat -> Cat) -> CFG -> CFG
mapCFGCats f cfg = mkCFG (f (cfgStartCat cfg))
(Set.map f (cfgExternalCats cfg))
[CFRule (f lhs) (map (mapSymbol f id) rhs) t | CFRule lhs rhs t <- allRules cfg]
mapCFGCats :: (Ord c,Ord c',Ord t) => (c -> c') -> Grammar c t -> Grammar c' t
mapCFGCats f cfg = Grammar (f (cfgStartCat cfg))
(Set.map f (cfgExternalCats cfg))
(groupProds [Rule (f lhs) (map (mapSymbol f id) rhs) t | Rule lhs rhs t <- allRules cfg])
onCFG :: (Map Cat (Set CFRule) -> Map Cat (Set CFRule)) -> CFG -> CFG
onCFG f cfg = cfg { cfgRules = f (cfgRules cfg) }
onRules :: ([CFRule] -> [CFRule]) -> CFG -> CFG
onRules :: (Ord c,Ord t) => ([Rule c t] -> [Rule c t]) -> Grammar c t -> Grammar c t
onRules f cfg = cfg { cfgRules = groupProds $ f $ allRules cfg }
-- | Clean up CFG after rules have been removed.
cleanCFG :: CFG -> CFG
cleanCFG = onCFG (Map.filter (not . Set.null))
cleanCFG :: Ord c => Grammar c t -> Grammar c t
cleanCFG cfg = cfg{ cfgRules = Map.filter (not . Set.null) (cfgRules cfg) }
-- | Combine two CFGs.
unionCFG :: CFG -> CFG -> CFG
unionCFG x y = onCFG (\rs -> Map.unionWith Set.union rs (cfgRules y)) x
unionCFG :: (Ord c,Ord t) => Grammar c t -> Grammar c t -> Grammar c t
unionCFG x y = x { cfgRules = Map.unionWith Set.union (cfgRules x) (cfgRules y) }
filterCFG :: (CFRule -> Bool) -> CFG -> CFG
filterCFG p = cleanCFG . onCFG (Map.map (Set.filter p))
filterCFG :: (Rule c t -> Bool) -> Grammar c t -> Grammar c t
filterCFG p cfg = cfg { cfgRules = Map.mapMaybe filterRules (cfgRules cfg) }
where
filterRules rules =
let rules' = Set.filter p rules
in if Set.null rules' then Nothing else Just rules'
filterCFGCats :: (Cat -> Bool) -> CFG -> CFG
filterCFGCats p = onCFG (Map.filterWithKey (\c _ -> p c))
filterCFGCats :: (c -> Bool) -> Grammar c t -> Grammar c t
filterCFGCats p cfg = cfg { cfgRules = Map.filterWithKey (\c _ -> p c) (cfgRules cfg) }
countCats :: CFG -> Int
countCats :: Ord c => Grammar c t -> Int
countCats = Map.size . cfgRules . cleanCFG
countRules :: CFG -> Int
countRules :: Grammar c t -> Int
countRules = length . allRules
prCFG :: CFG -> String
prCFG = prProductions . map prRule . allRules
where
prRule r = (lhsCat r, unwords (map prSym (ruleRhs r)))
prRule r = (ruleLhs r, unwords (map prSym (ruleRhs r)))
prSym = symbol id (\t -> "\""++ t ++"\"")
prProductions :: [(Cat,String)] -> String
@@ -325,8 +329,8 @@ prCFTerm = pr 0
-- * CFRule Utilities
--
ruleFun :: CFRule -> CId
ruleFun (CFRule _ _ t) = f t
ruleFun :: Rule c t -> CId
ruleFun (Rule _ _ t) = f t
where f (CFObj n _) = n
f (CFApp _ x) = f x
f (CFAbs _ x) = f x
@@ -334,29 +338,31 @@ ruleFun (CFRule _ _ t) = f t
-- | Check if any of the categories used on the right-hand side
-- are in the given list of categories.
anyUsedBy :: [Cat] -> CFRule -> Bool
anyUsedBy cs (CFRule _ ss _) = any (`elem` cs) (filterCats ss)
anyUsedBy :: Eq c => [c] -> Rule c t -> Bool
anyUsedBy cs (Rule _ ss _) = any (`elem` cs) (filterCats ss)
mkCFTerm :: String -> CFTerm
mkCFTerm n = CFObj (mkCId n) []
ruleIsNonRecursive :: Set Cat -> CFRule -> Bool
ruleIsNonRecursive :: Ord c => Set c -> Rule c t -> Bool
ruleIsNonRecursive cs = noCatsInSet cs . ruleRhs
-- | Check if all the rules are right-linear, or all the rules are
-- left-linear, with respect to given categories.
allXLinear :: Set Cat -> [CFRule] -> Bool
allXLinear :: Ord c => Set c -> [Rule c t] -> Bool
allXLinear cs rs = all (isRightLinear cs) rs || all (isLeftLinear cs) rs
-- | Checks if a context-free rule is right-linear.
isRightLinear :: Set Cat -- ^ The categories to consider
-> CFRule -- ^ The rule to check for right-linearity
isRightLinear :: Ord c
=> Set c -- ^ The categories to consider
-> Rule c t -- ^ The rule to check for right-linearity
-> Bool
isRightLinear cs = noCatsInSet cs . safeInit . ruleRhs
-- | Checks if a context-free rule is left-linear.
isLeftLinear :: Set Cat -- ^ The categories to consider
-> CFRule -- ^ The rule to check for left-linearity
isLeftLinear :: Ord c
=> Set c -- ^ The categories to consider
-> Rule c t -- ^ The rule to check for left-linearity
-> Bool
isLeftLinear cs = noCatsInSet cs . drop 1 . ruleRhs

18
src/compiler/GF/Grammar/EBNF.hs
View File

@@ -18,8 +18,6 @@ import GF.Data.Operations
import GF.Grammar.CFG
import PGF (mkCId)
import Data.List
type EBNF = [ERule]
type ERule = (ECat, ERHS)
type ECat = (String,[Int])
@@ -35,14 +33,14 @@ data ERHS =
| EOpt ERHS
| EEmpty
type CFRHS = [CFSymbol]
type CFJustRule = (Cat, CFRHS)
type CFRHS = [ParamCFSymbol]
type CFJustRule = ((Cat,[Param]), CFRHS)
ebnf2cf :: EBNF -> [CFRule]
ebnf2cf :: EBNF -> [ParamCFRule]
ebnf2cf ebnf =
[CFRule cat items (mkCFF i cat) | (i,(cat,items)) <- zip [0..] (normEBNF ebnf)]
[Rule cat items (mkCFF i cat) | (i,(cat,items)) <- zip [0..] (normEBNF ebnf)]
where
mkCFF i c = CFObj (mkCId ("Mk" ++ c ++ "_" ++ show i)) []
mkCFF i (c,_) = CFObj (mkCId ("Mk" ++ c ++ "_" ++ show i)) []
normEBNF :: EBNF -> [CFJustRule]
normEBNF erules = let
@@ -101,7 +99,7 @@ substERules g (cat,itss) = (cat, map sub itss) where
sub (EIPlus r : ii) = EIPlus (substERules g r) : ii
sub (EIOpt r : ii) = EIOpt (substERules g r) : ii
-}
eitem2cfitem :: EItem -> CFSymbol
eitem2cfitem :: EItem -> ParamCFSymbol
eitem2cfitem it = case it of
EITerm a -> Terminal a
EINonTerm cat -> NonTerminal (mkCFCatE cat)
@@ -143,8 +141,8 @@ mkECat ints = ("C", ints)
prECat (c,[]) = c
prECat (c,ints) = c ++ "_" ++ prTList "_" (map show ints)
mkCFCatE :: ECat -> Cat
mkCFCatE = prECat
mkCFCatE :: ECat -> (Cat,[Param])
mkCFCatE c = (prECat c,[0])
{-
updECat _ (c,[]) = (c,[])
updECat ii (c,_) = (c,ii)