diff --git a/src/GF/Speech/FiniteState.hs b/src/GF/Speech/FiniteState.hs index cfcc6e096..dfd5d941d 100644 --- a/src/GF/Speech/FiniteState.hs +++ b/src/GF/Speech/FiniteState.hs @@ -18,6 +18,7 @@ module GF.Speech.FiniteState (FA, State, NFA, DFA, addFinalState, newState, newTransition, mapStates, mapTransitions, + oneFinalState, moveLabelsToNodes, minimize, dfa2nfa, prFAGraphviz) where @@ -79,6 +80,18 @@ minimize = determinize . reverseNFA . dfa2nfa . determinize . reverseNFA onGraph :: (Graph n a b -> Graph n c d) -> FA n a b -> FA n c d onGraph f (FA g s ss) = FA (f g) s ss +-- | Make the finite automaton have a single final state +-- by adding a new final state and adding an edge +-- from the old final states to the new state. +oneFinalState :: a -- ^ Label to give the new node + -> b -- ^ Label to give the new edges + -> FA n a b -- ^ The old network + -> FA n a b -- ^ The new network +oneFinalState nl el fa = + let (FA g s fs,nf) = newState nl fa + es = [ (f,nf,el) | f <- fs ] + in FA (newEdges es g) s [nf] + -- | Transform a standard finite automaton with labelled edges -- to one where the labels are on the nodes instead. This can add -- up to one extra node per edge. diff --git a/src/GF/Speech/PrSLF.hs b/src/GF/Speech/PrSLF.hs index eba50a7e8..1e614d140 100644 --- a/src/GF/Speech/PrSLF.hs +++ b/src/GF/Speech/PrSLF.hs @@ -48,12 +48,16 @@ data SLFEdge = SLFEdge { eId :: Int, eStart :: Int, eEnd :: Int } slfPrinter :: Ident -- ^ Grammar name -> Options -> CGrammar -> String -slfPrinter name opts cfg = prSLF (automatonToSLF $ moveLabelsToNodes $ dfa2nfa $ cfgToFA name opts cfg) "" +slfPrinter name opts cfg = prSLF (automatonToSLF $ mkSLFFA name opts cfg) "" slfGraphvizPrinter :: Ident -- ^ Grammar name -> Options -> CGrammar -> String slfGraphvizPrinter name opts cfg = - prFAGraphviz $ mapStates (fromMaybe "") $ mapTransitions (const "") $ moveLabelsToNodes $ dfa2nfa $ cfgToFA name opts cfg + prFAGraphviz $ mapStates (fromMaybe "") $ mapTransitions (const "") $ mkSLFFA name opts cfg + +mkSLFFA :: Ident -- ^ Grammar name + -> Options -> CGrammar -> FA State (Maybe String) () +mkSLFFA name opts cfg = oneFinalState Nothing () $ moveLabelsToNodes $ dfa2nfa $ cfgToFA name opts cfg automatonToSLF :: FA State (Maybe String) () -> SLF automatonToSLF fa =