forked from GitHub/gf-core
Completed unoptimized SLF generation.
This commit is contained in:
bringert
171
src/GF/Speech/CFGToFiniteState.hs
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171
src/GF/Speech/CFGToFiniteState.hs
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@@ -0,0 +1,171 @@
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----------------------------------------------------------------------
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-- |
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-- Module : CFGToFiniteState
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-- Maintainer : BB
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-- Stability : (stable)
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-- Portability : (portable)
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--
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-- > CVS $Date: 2005/09/12 15:46:44 $
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-- > CVS $Author: bringert $
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-- > CVS $Revision: 1.1 $
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--
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-- Approximates CFGs with finite state networks.
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-----------------------------------------------------------------------------
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module GF.Speech.CFGToFiniteState (cfgToFA) where
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import Data.List
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import GF.Formalism.CFG
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import GF.Formalism.Utilities (Symbol(..), mapSymbol, filterCats, symbol, NameProfile(..))
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import GF.Conversion.Types
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import GF.Infra.Ident (Ident)
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import GF.Infra.Option (Options)
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import GF.Speech.FiniteState
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import GF.Speech.TransformCFG
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cfgToFA :: Ident -- ^ Grammar name
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-> Options -> CGrammar -> FA () (Maybe String)
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cfgToFA name opts cfg = minimize $ compileAutomaton start rgr
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where start = getStartCat opts
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rgr = makeRegular $ removeIdenticalRules $ removeEmptyCats $ cfgToCFRules cfg
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-- Use the transformation algorithm from \"Regular Approximation of Context-free
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-- Grammars through Approximation\", Mohri and Nederhof, 2000
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-- to create an over-generating regular frammar for a context-free
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-- grammar
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makeRegular :: CFRules -> CFRules
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makeRegular g = groupProds $ concatMap trSet (mutRecCats True g)
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where trSet cs | allXLinear cs rs = rs
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| otherwise = concatMap handleCat cs
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where rs = catSetRules g cs
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handleCat c = [CFRule c' [] (mkName (c++"-empty"))] -- introduce A' -> e
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++ concatMap (makeRightLinearRules c) (catRules g c)
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where c' = newCat c
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makeRightLinearRules b' (CFRule c ss n) =
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case ys of
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[] -> [CFRule b' (xs ++ [Cat (newCat c)]) n] -- no non-terminals left
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(Cat b:zs) -> CFRule b' (xs ++ [Cat b]) n
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: makeRightLinearRules (newCat b) (CFRule c zs n)
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where (xs,ys) = break (`catElem` cs) ss
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newCat c = c ++ "$"
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-- | Get the sets of mutually recursive non-terminals for a grammar.
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mutRecCats :: Bool -- ^ If true, all categories will be in some set.
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-- If false, only recursive categories will be included.
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-> CFRules -> [[Cat_]]
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mutRecCats incAll g = equivalenceClasses $ symmetricSubrelation $ transitiveClosure r'
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where r = nub [(c,c') | (_,rs) <- g, CFRule c ss _ <- rs, Cat c' <- ss]
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allCats = map fst g
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r' = (if incAll then reflexiveClosure allCats else id) r
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-- Convert a strongly regular grammar to a finite automaton.
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compileAutomaton :: Cat_ -- ^ Start category
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-> CFRules
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-> FA () (Maybe Token)
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compileAutomaton start g = make_fa s [Cat start] f fa''
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where fa = newFA ()
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s = startState fa
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(fa',f) = newState () fa
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fa'' = addFinalState f fa'
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ns = mutRecCats False g
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-- | The make_fa algorithm from \"Regular approximation of CFLs: a grammatical view\",
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-- Mark-Jan Nederhof. International Workshop on Parsing Technologies, 1997.
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make_fa :: State -> [Symbol Cat_ Token] -> State
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-> FA () (Maybe Token) -> FA () (Maybe Token)
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make_fa q0 alpha q1 fa =
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case alpha of
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[] -> newTransition q0 q1 Nothing fa
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[Tok t] -> newTransition q0 q1 (Just t) fa
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[Cat a] -> case findSet a ns of
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-- a is recursive
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Just ni -> let (fa',ss) = addStatesForCats ni fa
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getState x = lookup' x ss
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niRules = catSetRules g ni
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(nrs,rs) = partition (ruleIsNonRecursive ni) niRules
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in if all (isRightLinear ni) niRules then
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-- the set Ni is right-recursive or cyclic
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let fa'' = foldFuns [make_fa (getState c) xs q1 | CFRule c xs _ <- nrs] fa'
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fa''' = foldFuns [make_fa (getState c) xs (getState d) | CFRule c ss _ <- rs,
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let (xs,Cat d) = (init ss,last ss)] fa''
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in newTransition q0 (getState a) Nothing fa'''
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else
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-- the set Ni is left-recursive
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let fa'' = foldFuns [make_fa q0 xs (getState c) | CFRule c xs _ <- nrs] fa'
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fa''' = foldFuns [make_fa (getState d) xs (getState c) | CFRule c (Cat d:xs) _ <- rs] fa''
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in newTransition (getState a) q1 Nothing fa'''
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-- a is not recursive
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Nothing -> let rs = catRules g a
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in foldr (\ (CFRule _ b _) -> make_fa q0 b q1) fa rs
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(x:beta) -> let (fa',q) = newState () fa
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in make_fa q beta q1 $ make_fa q0 [x] q fa'
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addStatesForCats [] fa = (fa,[])
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addStatesForCats (c:cs) fa = let (fa',s) = newState () fa
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(fa'',ss) = addStatesForCats cs fa'
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in (fa'',(c,s):ss)
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ruleIsNonRecursive cs = noCatsInSet cs . ruleRhs
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noCatsInSet :: Eq c => [c] -> [Symbol c t] -> Bool
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noCatsInSet cs = not . any (`catElem` cs)
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-- | Check if all the rules are right-linear, or all the rules are
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-- left-linear, with respect to given categories.
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allXLinear :: Eq c => [c] -> [CFRule c n t] -> Bool
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allXLinear cs rs = all (isRightLinear cs) rs || all (isLeftLinear cs) rs
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-- | Checks if a context-free rule is right-linear.
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isRightLinear :: Eq c => [c] -- ^ The categories to consider
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-> CFRule c n t -- ^ The rule to check for right-linearity
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-> Bool
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isRightLinear cs = noCatsInSet cs . safeInit . ruleRhs
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-- | Checks if a context-free rule is left-linear.
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isLeftLinear :: Eq c => [c] -- ^ The categories to consider
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-> CFRule c n t -- ^ The rule to check for right-linearity
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-> Bool
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isLeftLinear cs = noCatsInSet cs . drop 1 . ruleRhs
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--
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-- * Relations
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--
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-- FIXME: these could use a more efficent data structures and algorithms.
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type Rel a = [(a,a)]
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isRelatedTo :: Eq a => Rel a -> a -> a -> Bool
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isRelatedTo r x y = (x,y) `elem` r
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transitiveClosure :: Eq a => Rel a -> Rel a
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transitiveClosure r = fix (\r -> r `union` [ (x,w) | (x,y) <- r, (z,w) <- r, y == z ]) r
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reflexiveClosure :: Eq a => [a] -- ^ The set over which the relation is defined.
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-> Rel a -> Rel a
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reflexiveClosure u r = [(x,x) | x <- u] `union` r
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symmetricSubrelation :: Eq a => Rel a -> Rel a
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symmetricSubrelation r = [p | p@(x,y) <- r, (y,x) `elem` r]
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-- | Get the equivalence classes from an equivalence relation. Since
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-- the relation is relexive, the set can be recoved from the relation.
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equivalenceClasses :: Eq a => Rel a -> [[a]]
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equivalenceClasses r = equivalenceClasses_ (nub (map fst r)) r
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where equivalenceClasses_ [] _ = []
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equivalenceClasses_ (x:xs) r = (x:ys):equivalenceClasses_ zs r
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where (ys,zs) = partition (isRelatedTo r x) xs
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--
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-- * Utilities
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--
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foldFuns :: [a -> a] -> a -> a
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foldFuns fs x = foldr ($) x fs
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safeInit :: [a] -> [a]
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safeInit [] = []
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safeInit xs = init xs
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@@ -1,9 +1,22 @@
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----------------------------------------------------------------------
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-- |
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-- Module : FiniteState
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-- Maintainer : BB
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-- Stability : (stable)
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-- Portability : (portable)
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--
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-- > CVS $Date: 2005/09/12 15:46:44 $
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-- > CVS $Author: bringert $
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-- > CVS $Revision: 1.3 $
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--
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-- A simple finite state network module.
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-----------------------------------------------------------------------------
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module GF.Speech.FiniteState (FA, State,
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startState, finalStates,
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states, transitions,
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newFA, addFinalState,
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newState, newTrans,
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moveLabelsToNodes) where
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newState, newTransition, newTransitions,
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moveLabelsToNodes, minimize, asGraph) where
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import Data.Graph.Inductive
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import Data.List (nub,partition)
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@@ -41,8 +54,20 @@ newState :: a -> FA a b -> (FA a b, State)
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newState x (FA g s ss) = (FA g' s ss, n)
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where (g',n) = addNode x g
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newTrans :: Node -> Node -> b -> FA a b -> FA a b
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newTrans f t l = onGraph (insEdge (f,t,l))
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newTransition :: Node -> Node -> b -> FA a b -> FA a b
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newTransition f t l = onGraph (insEdge (f,t,l))
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newTransitions :: [(Node,Node,b)] -> FA a b -> FA a b
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newTransitions ts = onGraph (insEdges ts)
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mapStates :: (a -> c) -> FA a b -> FA c b
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mapStates f (FA g s ss) = FA (nmap f g) s ss
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asGraph :: FA a b -> Gr a b
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asGraph (FA g _ _) = g
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minimize :: FA () (Maybe a) -> FA () (Maybe a)
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minimize = onGraph mimimizeGr1
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--
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-- * Graph functions
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@@ -111,6 +136,17 @@ ledgeToEdge (f,t,_) = (f,t)
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addContexts :: DynGraph gr => [Context a b] -> gr a b -> gr a b
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addContexts cs gr = foldr (&) gr cs
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mimimizeGr1 :: DynGraph gr => gr () (Maybe a) -> gr () (Maybe a)
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mimimizeGr1 = removeEmptyLoops
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removeEmptyLoops :: DynGraph gr => gr () (Maybe a) -> gr () (Maybe a)
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removeEmptyLoops = gmap (\ (i,n,(),o) -> (filter (r n) i,n,(),filter (r n) o))
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where r n (Nothing,n') | n' == n = False
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r _ _ = True
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mimimizeGr2 :: DynGraph gr => gr (Maybe a) () -> gr (Maybe a) ()
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mimimizeGr2 gr = gr
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--
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-- * Utilities
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--
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@@ -5,9 +5,9 @@
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-- Stability : (stable)
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-- Portability : (portable)
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--
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-- > CVS $Date: 2005/09/07 14:21:30 $
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-- > CVS $Date: 2005/09/12 15:46:44 $
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-- > CVS $Author: bringert $
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-- > CVS $Revision: 1.3 $
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-- > CVS $Revision: 1.4 $
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--
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-- This module converts a CFG to an SLF finite-state network
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-- for use with the ATK recognizer. The SLF format is described
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@@ -18,10 +18,11 @@
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-- categories in the grammar
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-----------------------------------------------------------------------------
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module GF.Speech.PrSLF (slfPrinter) where
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module GF.Speech.PrSLF (slfPrinter,slfGraphvizPrinter,faGraphvizPrinter) where
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import GF.Speech.SRG
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import GF.Speech.TransformCFG
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import GF.Speech.CFGToFiniteState
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import GF.Speech.FiniteState
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import GF.Infra.Ident
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@@ -34,6 +35,9 @@ import GF.Infra.Option
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import Data.Char (toUpper,toLower)
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import Data.Maybe (fromMaybe)
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import Data.Graph.Inductive (emap,nmap)
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import Data.Graph.Inductive.Graphviz
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data SLF = SLF { slfNodes :: [SLFNode], slfEdges :: [SLFEdge] }
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data SLFNode = SLFNode { nId :: Int, nWord :: SLFWord }
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@@ -46,31 +50,35 @@ data SLFEdge = SLFEdge { eId :: Int, eStart :: Int, eEnd :: Int }
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slfPrinter :: Ident -- ^ Grammar name
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-> Options -> CGrammar -> String
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slfPrinter name opts cfg = prSLF (regularToSLF start rgr) ""
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where start = getStartCat opts
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rgr = makeRegular $ removeEmptyCats $ cfgToCFRules cfg
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slfPrinter name opts cfg = prSLF (automatonToSLF $ moveLabelsToNodes $ cfgToFA name opts cfg) ""
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regularToSLF :: String -> CFRules -> SLF
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regularToSLF s rs = automatonToSLF $ compileAutomaton s rs
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slfGraphvizPrinter :: Ident -- ^ Grammar name
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-> Options -> CGrammar -> String
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slfGraphvizPrinter name opts cfg =
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graphviz (nmap (fromMaybe "") $ asGraph $ moveLabelsToNodes $ cfgToFA name opts cfg) (prIdent name) (8.5,11.0) (1,1) Landscape
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automatonToSLF :: FA () (Maybe String) -> SLF
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faGraphvizPrinter :: Ident -- ^ Grammar name
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-> Options -> CGrammar -> String
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faGraphvizPrinter name opts cfg =
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graphviz (nmap (const "") $ emap (fromMaybe "") $ asGraph $ cfgToFA name opts cfg) (prIdent name) (8.5,11.0) (1,1) Landscape
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automatonToSLF :: FA (Maybe String) () -> SLF
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automatonToSLF fa =
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SLF { slfNodes = map mkSLFNode (states fa'),
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slfEdges = zipWith mkSLFEdge [0..] (transitions fa') }
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where fa' = moveLabelsToNodes fa
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mkSLFNode (i,w) = SLFNode { nId = i, nWord = w }
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SLF { slfNodes = map mkSLFNode (states fa),
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slfEdges = zipWith mkSLFEdge [0..] (transitions fa) }
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where mkSLFNode (i,w) = SLFNode { nId = i, nWord = w }
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mkSLFEdge i (f,t,()) = SLFEdge { eId = i, eStart = f, eEnd = t }
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prSLF :: SLF -> ShowS
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prSLF (SLF { slfNodes = ns, slfEdges = es}) = header . unlinesS (map prNode ns) . unlinesS (map prEdge es)
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prSLF (SLF { slfNodes = ns, slfEdges = es})
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= header . unlinesS (map prNode ns) . nl . unlinesS (map prEdge es) . nl
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where
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header = showString "VERSION=1.0" . nl
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. prFields [("N",show (length ns)),("L", show (length es))] . nl
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prNode n = prFields [("I",show (nId n)),("W",showWord (nWord n))]
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prEdge e = prFields [("J",show (eId e)),("S",show (eStart e)),("E",show (eEnd e))]
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showWord :: SLFWord -> String
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showWord Nothing = "!NULL"
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showWord (Just w) = w -- FIXME: convert words to upper case
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@@ -5,9 +5,9 @@
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-- Stability : (stable)
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-- Portability : (portable)
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--
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-- > CVS $Date: 2005/09/07 14:21:30 $
|
||||
-- > CVS $Date: 2005/09/12 15:46:44 $
|
||||
-- > CVS $Author: bringert $
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-- > CVS $Revision: 1.15 $
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-- > CVS $Revision: 1.16 $
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--
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-- Representation of, conversion to, and utilities for
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-- printing of a general Speech Recognition Grammar.
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@@ -58,24 +58,18 @@ makeSRG i opts gr = SRG { grammarName = name,
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where
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name = prIdent i
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origStart = getStartCat opts
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gr' = removeLeftRecursion $ removeEmptyCats $ cfgToCFRules gr
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gr' = removeLeftRecursion $ removeIdenticalRules $ removeEmptyCats $ cfgToCFRules gr
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(cats,cfgRules) = unzip gr'
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names = mkCatNames name cats
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cfgRulesToSRGRule :: FiniteMap String String -> [CFRule_] -> SRGRule
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cfgRulesToSRGRule names rs@(r:_) = SRGRule cat origCat rhs
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where origCat = ruleCat r
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where origCat = lhsCat r
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cat = lookupFM_ names origCat
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rhs = nub $ map (map renameCat . ruleRhs) rs
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renameCat (Cat c) = Cat (lookupFM_ names c)
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renameCat t = t
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ruleCat :: CFRule c n t -> c
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ruleCat (CFRule c _ _) = c
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ruleRhs :: CFRule c n t -> [Symbol c t]
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ruleRhs (CFRule _ r _) = r
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mkCatNames :: String -- ^ Category name prefix
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-> [String] -- ^ Original category names
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-> FiniteMap String String -- ^ Maps original names to SRG names
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@@ -5,9 +5,9 @@
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-- Stability : (stable)
|
||||
-- Portability : (portable)
|
||||
--
|
||||
-- > CVS $Date: 2005/09/08 15:45:17 $
|
||||
-- > CVS $Date: 2005/09/12 15:46:44 $
|
||||
-- > CVS $Author: bringert $
|
||||
-- > CVS $Revision: 1.19 $
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-- > CVS $Revision: 1.20 $
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--
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-- This module does some useful transformations on CFGs.
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--
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@@ -16,12 +16,12 @@
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-- peb thinks: most of this module should be moved to GF.Conversion...
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-----------------------------------------------------------------------------
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module GF.Speech.TransformCFG (CFRule_, CFRules,
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-- FIXME: lots of this stuff is used by CFGToFiniteState, thus
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-- the missing explicit expot list.
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module GF.Speech.TransformCFG {- (CFRule_, CFRules,
|
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cfgToCFRules, getStartCat,
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removeLeftRecursion,
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removeEmptyCats,
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||||
makeRegular,
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compileAutomaton) where
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removeEmptyCats, removeIdenticalRules) -} where
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import GF.Infra.Ident
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import GF.Formalism.CFG
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@@ -62,8 +62,6 @@ groupProds = fmToList . addListToFM_C (++) emptyFM . map (\r -> (lhsCat r,[r]))
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ungroupProds :: CFRules -> [CFRule_]
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ungroupProds = concat . map snd
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catRules :: CFRules -> Cat_ -> [CFRule_]
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catRules rs c = fromMaybe [] (lookup c rs)
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-- | Remove productions which use categories which have no productions
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removeEmptyCats :: CFRules -> CFRules
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@@ -77,13 +75,18 @@ removeEmptyCats = fix removeEmptyCats'
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emptyCats = filter (nothingOrNull . flip lookup rs) allCats
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k' = map (\ (c,xs) -> (c, filter (not . anyUsedBy emptyCats) xs)) keep
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||||
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||||
-- | Remove rules which are identical, not caring about the rule names.
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||||
removeIdenticalRules :: CFRules -> CFRules
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removeIdenticalRules g = [(c,nubBy sameCatAndRhs rs) | (c,rs) <- g]
|
||||
where sameCatAndRhs (CFRule c1 ss1 _) (CFRule c2 ss2 _) = c1 == c2 && ss1 == ss2
|
||||
|
||||
removeLeftRecursion :: CFRules -> CFRules
|
||||
removeLeftRecursion rs = concatMap removeDirectLeftRecursion $ map handleProds rs
|
||||
where
|
||||
handleProds (c, r) = (c, concatMap handleProd r)
|
||||
handleProd (CFRule ai (Cat aj:alpha) n) | aj < ai =
|
||||
-- FIXME: this will give multiple rules with the same name
|
||||
[CFRule ai (beta ++ alpha) n | CFRule _ beta _ <- fromJust (lookup aj rs)]
|
||||
[CFRule ai (beta ++ alpha) n | CFRule _ beta _ <- lookup' aj rs]
|
||||
handleProd r = [r]
|
||||
|
||||
removeDirectLeftRecursion :: (Cat_,[CFRule_]) -- ^ All productions for a category
|
||||
@@ -103,92 +106,22 @@ isDirectLeftRecursive (CFRule c (Cat c':_) _) = c == c'
|
||||
isDirectLeftRecursive _ = False
|
||||
|
||||
|
||||
-- Use the transformation algorithm from \"Regular Approximation of Context-free
|
||||
-- Grammars through Approximation\", Mohri and Nederhof, 2000
|
||||
-- to create an over-generating regular frammar for a context-free
|
||||
-- grammar
|
||||
makeRegular :: CFRules -> CFRules
|
||||
makeRegular g = groupProds $ concatMap trSet (mutRecCats g)
|
||||
where trSet cs | allXLinear cs rs = rs
|
||||
| otherwise = concatMap handleCat cs
|
||||
where rs = concatMap (catRules g) cs
|
||||
handleCat c = [CFRule c' [] (mkName (c++"-empty"))] -- introduce A' -> e
|
||||
++ concatMap (makeRightLinearRules c) (catRules g c)
|
||||
where c' = newCat c
|
||||
makeRightLinearRules b' (CFRule c ss n) =
|
||||
case ys of
|
||||
[] -> [CFRule b' (xs ++ [Cat (newCat c)]) n] -- no non-terminals left
|
||||
(Cat b:zs) -> CFRule b' (xs ++ [Cat b]) n
|
||||
: makeRightLinearRules (newCat b) (CFRule c zs n)
|
||||
where (xs,ys) = break (`catElem` cs) ss
|
||||
newCat c = c ++ "$"
|
||||
|
||||
|
||||
-- | Get the sets of mutually recursive non-terminals for a grammar.
|
||||
mutRecCats :: CFRules -> [[Cat_]]
|
||||
mutRecCats g = equivalenceClasses $ symmetricSubrelation $ transitiveClosure $ reflexiveClosure allCats r
|
||||
where r = nub [(c,c') | (_,rs) <- g, CFRule c ss _ <- rs, Cat c' <- ss]
|
||||
allCats = map fst g
|
||||
|
||||
|
||||
|
||||
-- Convert a strongly regular grammar to a finite automaton.
|
||||
compileAutomaton :: Cat_ -- ^ Start category
|
||||
-> CFRules
|
||||
-> FA () (Maybe Token)
|
||||
compileAutomaton start g = make_fa s [Cat start] f g fa''
|
||||
where fa = newFA ()
|
||||
s = startState fa
|
||||
(fa',f) = newState () fa
|
||||
fa'' = addFinalState f fa'
|
||||
|
||||
-- | The make_fa algorithm from \"Regular approximation of CFLs: a grammatical view\",
|
||||
-- Mark-Jan Nederhof. International Workshop on Parsing Technologies, 1997.
|
||||
make_fa :: State -> [Symbol Cat_ Token] -> State
|
||||
-> CFRules -> FA () (Maybe Token) -> FA () (Maybe Token)
|
||||
make_fa q0 a q1 g fa =
|
||||
case a of
|
||||
[] -> newTrans q0 q1 Nothing fa
|
||||
[Tok t] -> newTrans q0 q1 (Just t) fa
|
||||
[Cat c] -> undefined
|
||||
(x:beta) -> let (fa',q) = newState () fa
|
||||
fa'' = make_fa q0 [x] q g fa'
|
||||
fa''' = make_fa q beta q1 g fa''
|
||||
in fa'''
|
||||
|
||||
--
|
||||
-- * CFG rule utilities
|
||||
--
|
||||
|
||||
{-
|
||||
-- | Get all the rules for a given category.
|
||||
catRules :: Eq c => [CFRule c n t] -> c -> [CFRule c n t]
|
||||
catRules rs c = [r | r@(CFRule c' _ _) <- rs, c' == c]
|
||||
-}
|
||||
catRules :: CFRules -> Cat_ -> [CFRule_]
|
||||
catRules rs c = fromMaybe [] (lookup c rs)
|
||||
|
||||
-- | Gets the set of LHS categories of a set of rules.
|
||||
lhsCats :: Eq c => [CFRule c n t] -> [c]
|
||||
lhsCats = nub . map lhsCat
|
||||
catSetRules :: CFRules -> [Cat_] -> [CFRule_]
|
||||
catSetRules g s = concatMap (catRules g) s
|
||||
|
||||
lhsCat :: CFRule c n t -> c
|
||||
lhsCat (CFRule c _ _) = c
|
||||
|
||||
-- | Check if all the rules are right-linear, or all the rules are
|
||||
-- left-linear, with respect to given categories.
|
||||
allXLinear :: Eq c => [c] -> [CFRule c n t] -> Bool
|
||||
allXLinear cs rs = all (isRightLinear cs) rs || all (isLeftLinear cs) rs
|
||||
ruleRhs :: CFRule c n t -> [Symbol c t]
|
||||
ruleRhs (CFRule _ ss _) = ss
|
||||
|
||||
-- | Checks if a context-free rule is right-linear.
|
||||
isRightLinear :: Eq c => [c] -- ^ The categories to consider
|
||||
-> CFRule c n t -- ^ The rule to check for right-linearity
|
||||
-> Bool
|
||||
isRightLinear cs (CFRule _ ss _) = all (not . (`catElem` cs)) (safeInit ss)
|
||||
|
||||
-- | Checks if a context-free rule is left-linear.
|
||||
isLeftLinear :: Eq c => [c] -- ^ The categories to consider
|
||||
-> CFRule c n t -- ^ The rule to check for right-linearity
|
||||
-> Bool
|
||||
isLeftLinear cs (CFRule _ ss _) = all (not . (`catElem` cs)) (drop 1 ss)
|
||||
|
||||
-- | Checks if a symbol is a non-terminal of one of the given categories.
|
||||
catElem :: Eq c => Symbol c t -> [c] -> Bool
|
||||
@@ -202,37 +135,14 @@ anyUsedBy cs (CFRule _ ss _) = any (`elem` cs) (filterCats ss)
|
||||
mkName :: String -> Name
|
||||
mkName n = Name (IC n) []
|
||||
|
||||
--
|
||||
-- * Relations
|
||||
--
|
||||
|
||||
-- FIXME: these could use a more efficent data structures and algorithms.
|
||||
|
||||
isRelatedTo :: Eq a => [(a,a)] -> a -> a -> Bool
|
||||
isRelatedTo r x y = (x,y) `elem` r
|
||||
|
||||
transitiveClosure :: Eq a => [(a,a)] -> [(a,a)]
|
||||
transitiveClosure r = fix (\r -> r `union` [ (x,w) | (x,y) <- r, (z,w) <- r, y == z ]) r
|
||||
|
||||
reflexiveClosure :: Eq a => [a] -- ^ The set over which the relation is defined.
|
||||
-> [(a,a)] -> [(a,a)]
|
||||
reflexiveClosure u r = [(x,x) | x <- u] `union` r
|
||||
|
||||
symmetricSubrelation :: Eq a => [(a,a)] -> [(a,a)]
|
||||
symmetricSubrelation r = [p | p@(x,y) <- r, (y,x) `elem` r]
|
||||
|
||||
-- | Get the equivalence classes from an equivalence relation. Since
|
||||
-- the relation is relexive, the set can be recoved from the relation.
|
||||
equivalenceClasses :: Eq a => [(a,a)] -> [[a]]
|
||||
equivalenceClasses r = equivalenceClasses_ (nub (map fst r)) r
|
||||
where equivalenceClasses_ [] _ = []
|
||||
equivalenceClasses_ (x:xs) r = (x:ys):equivalenceClasses_ zs r
|
||||
where (ys,zs) = partition (isRelatedTo r x) xs
|
||||
|
||||
--
|
||||
-- * Utilities
|
||||
--
|
||||
|
||||
findSet :: Eq c => c -> [[c]] -> Maybe [c]
|
||||
findSet x = find (x `elem`)
|
||||
|
||||
fix :: Eq a => (a -> a) -> a -> a
|
||||
fix f x = let x' = f x in if x' == x then x else fix f x'
|
||||
|
||||
@@ -240,26 +150,12 @@ nothingOrNull :: Maybe [a] -> Bool
|
||||
nothingOrNull Nothing = True
|
||||
nothingOrNull (Just xs) = null xs
|
||||
|
||||
safeInit :: [a] -> [a]
|
||||
safeInit [] = []
|
||||
safeInit xs = init xs
|
||||
|
||||
unionAll :: Eq a => [[a]] -> [a]
|
||||
unionAll = nub . concat
|
||||
|
||||
whenMP :: MonadPlus m => Bool -> a -> m a
|
||||
whenMP b x = if b then return x else mzero
|
||||
|
||||
--
|
||||
-- * Testing stuff, can be removed
|
||||
--
|
||||
lookup' :: Eq a => a -> [(a,b)] -> b
|
||||
lookup' x = fromJust . lookup x
|
||||
|
||||
c --> ss = CFRule c ss (mkName "")
|
||||
|
||||
prGr g = putStrLn $ showGr g
|
||||
|
||||
showGr g = unlines $ map showRule g
|
||||
|
||||
showRule (CFRule c ss _) = c ++ " --> " ++ unwords (map showSym ss)
|
||||
|
||||
showSym s = symbol id show s
|
||||
@@ -5,9 +5,9 @@
|
||||
-- Stability : (stable)
|
||||
-- Portability : (portable)
|
||||
--
|
||||
-- > CVS $Date: 2005/09/04 11:45:38 $
|
||||
-- > CVS $Author: aarne $
|
||||
-- > CVS $Revision: 1.70 $
|
||||
-- > CVS $Date: 2005/09/12 15:46:44 $
|
||||
-- > CVS $Author: bringert $
|
||||
-- > CVS $Revision: 1.71 $
|
||||
--
|
||||
-- A database for customizable GF shell commands.
|
||||
--
|
||||
@@ -57,7 +57,7 @@ import GF.Canon.MkGFC
|
||||
import GF.CF.CFtoSRG
|
||||
import GF.Speech.PrGSL (gslPrinter)
|
||||
import GF.Speech.PrJSGF (jsgfPrinter)
|
||||
import GF.Speech.PrSLF (slfPrinter)
|
||||
import GF.Speech.PrSLF (slfPrinter,slfGraphvizPrinter,faGraphvizPrinter)
|
||||
|
||||
import GF.Data.Zipper
|
||||
|
||||
@@ -241,6 +241,12 @@ customGrammarPrinter =
|
||||
,(strCI "slf", \s -> let opts = stateOptions s
|
||||
name = cncId s
|
||||
in slfPrinter name opts $ stateCFG s)
|
||||
,(strCI "slf_graphviz", \s -> let opts = stateOptions s
|
||||
name = cncId s
|
||||
in slfGraphvizPrinter name opts $ stateCFG s)
|
||||
,(strCI "fa_graphviz", \s -> let opts = stateOptions s
|
||||
name = cncId s
|
||||
in faGraphvizPrinter name opts $ stateCFG s)
|
||||
,(strCI "plbnf", prLBNF True)
|
||||
,(strCI "lbnf", prLBNF False)
|
||||
,(strCI "bnf", prBNF False)
|
||||
|
||||
Reference in New Issue
Block a user