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Diffstat (limited to 'src-3.0/GF/Speech/SRG.hs')
| -rw-r--r-- | src-3.0/GF/Speech/SRG.hs | 175 |
1 files changed, 175 insertions, 0 deletions
diff --git a/src-3.0/GF/Speech/SRG.hs b/src-3.0/GF/Speech/SRG.hs new file mode 100644 index 000000000..5816c0cb5 --- /dev/null +++ b/src-3.0/GF/Speech/SRG.hs @@ -0,0 +1,175 @@ +---------------------------------------------------------------------- +-- | +-- Module : SRG +-- +-- Representation of, conversion to, and utilities for +-- printing of a general Speech Recognition Grammar. +-- +-- FIXME: remove \/ warn \/ fail if there are int \/ string literal +-- categories in the grammar +---------------------------------------------------------------------- +module GF.Speech.SRG (SRG(..), SRGRule(..), SRGAlt(..), SRGItem + , SRGNT, CFTerm + , makeSRG + , makeSimpleSRG + , makeNonRecursiveSRG + , lookupFM_, prtS + ) where + +import GF.Data.Operations +import GF.Data.Utilities +import GF.Infra.Ident +import GF.Infra.PrintClass +import GF.Speech.CFG +import GF.Speech.PGFToCFG +import GF.Speech.Relation +import GF.Speech.FiniteState +import GF.Speech.RegExp +import GF.Speech.CFGToFA +import GF.Infra.Option +import PGF.CId +import PGF.Data +import PGF.Macros + +import Data.List +import Data.Maybe (fromMaybe, maybeToList) +import Data.Map (Map) +import qualified Data.Map as Map +import Data.Set (Set) +import qualified Data.Set as Set + +import Debug.Trace + +data SRG = SRG { srgName :: String -- ^ grammar name + , srgStartCat :: Cat -- ^ start category name + , srgExternalCats :: Set Cat + , srgLanguage :: Maybe String -- ^ The language for which the grammar + -- is intended, e.g. en-UK + , srgRules :: [SRGRule] + } + deriving (Eq,Show) + +data SRGRule = SRGRule Cat [SRGAlt] -- ^ SRG category name, original category name + -- and productions + deriving (Eq,Show) + +-- | maybe a probability, a rule name and an EBNF right-hand side +data SRGAlt = SRGAlt (Maybe Double) CFTerm SRGItem + deriving (Eq,Show) + +type SRGItem = RE SRGSymbol + +type SRGSymbol = Symbol SRGNT Token + +-- | An SRG non-terminal. Category name and its number in the profile. +type SRGNT = (Cat, Int) + + +-- | Create a non-left-recursive SRG. +-- FIXME: the probabilities in the returned +-- grammar may be meaningless. +makeSimpleSRG :: PGF + -> CId -- ^ Concrete syntax name. + -> SRG +makeSimpleSRG = makeSRG preprocess + where + preprocess = traceStats "After mergeIdentical" + . mergeIdentical + . traceStats "After removeLeftRecursion" + . removeLeftRecursion + . traceStats "After topDownFilter" + . topDownFilter + . traceStats "After bottomUpFilter" + . bottomUpFilter + . traceStats "After removeCycles" + . removeCycles + . traceStats "Inital CFG" + +traceStats s g = trace ("---- " ++ s ++ ": " ++ stats g {- ++ "\n" ++ prCFRules g ++ "----" -}) g + +stats g = "Categories: " ++ show (countCats g) + ++ " Rules: " ++ show (countRules g) + +makeNonRecursiveSRG :: PGF + -> CId -- ^ Concrete syntax name. + -> SRG +makeNonRecursiveSRG pgf cnc = + SRG { srgName = prCId cnc, + srgStartCat = start, + srgExternalCats = cfgExternalCats cfg, + srgLanguage = getSpeechLanguage pgf cnc, + srgRules = rs } + where + cfg = pgfToCFG pgf cnc + MFA start dfas = cfgToMFA cfg + rs = [SRGRule l [SRGAlt Nothing dummyCFTerm (dfaToSRGItem dfa)] | (l,dfa) <- dfas] + where dfaToSRGItem = mapRE dummySRGNT . minimizeRE . dfa2re + dummyCFTerm = CFMeta (mkCId "dummy") + dummySRGNT = mapSymbol (\c -> (c,0)) id + +makeSRG :: (CFG -> CFG) + -> PGF + -> CId -- ^ Concrete syntax name. + -> SRG +makeSRG preprocess pgf cnc = + SRG { srgName = prCId cnc, + srgStartCat = cfgStartCat cfg, + srgExternalCats = cfgExternalCats cfg, + srgLanguage = getSpeechLanguage pgf cnc, + srgRules = rs } + where + cfg = pgfToCFG pgf cnc + (_,cfgRules) = unzip $ allRulesGrouped $ preprocess cfg + rs = map cfRulesToSRGRule cfgRules + +getSpeechLanguage :: PGF -> CId -> Maybe String +getSpeechLanguage pgf cnc = fmap (replace '_' '-') $ lookConcrFlag pgf cnc (mkCId "language") + +cfRulesToSRGRule :: [CFRule] -> SRGRule +cfRulesToSRGRule rs@(r:_) = SRGRule (lhsCat r) rhs + where + alts = [((n,Nothing),mkSRGSymbols 0 ss) | CFRule c ss n <- rs] + rhs = [SRGAlt p n (srgItem sss) | ((n,p),sss) <- buildMultiMap alts ] + + mkSRGSymbols _ [] = [] + mkSRGSymbols i (NonTerminal c:ss) = NonTerminal (c,i) : mkSRGSymbols (i+1) ss + mkSRGSymbols i (Terminal t:ss) = Terminal t : mkSRGSymbols i ss + +allSRGCats :: SRG -> [String] +allSRGCats SRG { srgRules = rs } = [c | SRGRule c _ <- rs] + +-- +-- * Size-optimized EBNF SRGs +-- + +srgItem :: [[SRGSymbol]] -> SRGItem +srgItem = unionRE . map mergeItems . sortGroupBy (compareBy filterCats) +-- non-optimizing version: +--srgItem = unionRE . map seqRE + +-- | Merges a list of right-hand sides which all have the same +-- sequence of non-terminals. +mergeItems :: [[SRGSymbol]] -> SRGItem +mergeItems = minimizeRE . ungroupTokens . minimizeRE . unionRE . map seqRE . map groupTokens + +groupTokens :: [SRGSymbol] -> [Symbol SRGNT [Token]] +groupTokens [] = [] +groupTokens (Terminal t:ss) = case groupTokens ss of + Terminal ts:ss' -> Terminal (t:ts):ss' + ss' -> Terminal [t]:ss' +groupTokens (NonTerminal c:ss) = NonTerminal c : groupTokens ss + +ungroupTokens :: RE (Symbol SRGNT [Token]) -> RE SRGSymbol +ungroupTokens = joinRE . mapRE (symbol (RESymbol . NonTerminal) (REConcat . map (RESymbol . Terminal))) + +-- +-- * Utilities for building and printing SRGs +-- + +lookupFM_ :: (Ord key, Show key) => Map key elt -> key -> elt +lookupFM_ fm k = Map.findWithDefault err k fm + where err = error $ "Key not found: " ++ show k + ++ "\namong " ++ show (Map.keys fm) + +prtS :: Print a => a -> ShowS +prtS = showString . prt |