diff options
| author | bringert <bringert@cs.chalmers.se> | 2007-03-20 22:00:50 +0000 |
|---|---|---|
| committer | bringert <bringert@cs.chalmers.se> | 2007-03-20 22:00:50 +0000 |
| commit | 00e681aee886c3b12acbaf07068571238a955ed2 (patch) | |
| tree | bdb940d23e1bcfbe2fde12c58566f9327362323a /src | |
| parent | 50614d399a8270ad53ac577c6ad7f3563e8bee44 (diff) | |
Do the same initial transformations as for CFGs when generating FAs: remove cycles, identical rules and down top-down and bottom-up filtering.
Diffstat (limited to 'src')
| -rw-r--r-- | src/GF/Speech/CFGToFiniteState.hs | 16 | ||||
| -rw-r--r-- | src/GF/Speech/PrFA.hs | 2 |
2 files changed, 11 insertions, 7 deletions
diff --git a/src/GF/Speech/CFGToFiniteState.hs b/src/GF/Speech/CFGToFiniteState.hs index 872de48d0..d9f8c31fa 100644 --- a/src/GF/Speech/CFGToFiniteState.hs +++ b/src/GF/Speech/CFGToFiniteState.hs @@ -59,11 +59,15 @@ data MFA a = MFA (DFA (MFALabel a)) [(String,DFA (MFALabel a))] cfgToFA :: Options -> StateGrammar -> DFA String -cfgToFA opts s = minimize $ compileAutomaton start $ makeSimpleRegular s +cfgToFA opts s = minimize $ compileAutomaton start $ makeSimpleRegular opts s where start = getStartCatCF opts s -makeSimpleRegular :: StateGrammar -> CFRules -makeSimpleRegular = makeRegular . removeIdenticalRules . bottomUpFilter . cfgToCFRules +makeSimpleRegular :: Options -> StateGrammar -> CFRules +makeSimpleRegular opts s = makeRegular $ preprocess $ cfgToCFRules s + where start = getStartCatCF opts s + preprocess = fix (topDownFilter start . bottomUpFilter) + . removeIdenticalRules + . removeCycles -- -- * Approximate context-free grammars with regular grammars. @@ -148,7 +152,7 @@ make_fa c@(g,ns) q0 alpha q1 fa = -- cfgToMFA :: Options -> StateGrammar -> MFA String -cfgToMFA opts s = buildMFA start s +cfgToMFA opts s = buildMFA start $ makeSimpleRegular opts s where start = getStartCatCF opts s -- | Build a DFA by building and expanding an MFA @@ -156,11 +160,11 @@ cfgToFA' :: Options -> StateGrammar -> DFA String cfgToFA' opts s = mfaToDFA $ cfgToMFA opts s buildMFA :: Cat_ -- ^ Start category - -> StateGrammar -> MFA String + -> CFRules -> MFA String buildMFA start g = sortSubLats $ removeUnusedSubLats mfa where startFA = let (fa,s,f) = newFA_ in newTransition s f (MFASub start) fa - fas = compileAutomata $ makeSimpleRegular g + fas = compileAutomata g mkMFALabel (Cat c) = MFASub c mkMFALabel (Tok t) = MFASym t toMFA = mapTransitions mkMFALabel diff --git a/src/GF/Speech/PrFA.hs b/src/GF/Speech/PrFA.hs index aeb43fde2..382745a75 100644 --- a/src/GF/Speech/PrFA.hs +++ b/src/GF/Speech/PrFA.hs @@ -43,7 +43,7 @@ faGraphvizPrinter opts s = -- | Convert the grammar to a regular grammar and print it in BNF regularPrinter :: Options -> StateGrammar -> String -regularPrinter opts s = prCFRules $ makeSimpleRegular s +regularPrinter opts s = prCFRules $ makeSimpleRegular opts s where prCFRules :: CFRules -> String prCFRules g = unlines [ c ++ " ::= " ++ join " | " (map (showRhs . ruleRhs) rs) | (c,rs) <- g] |