Generalized Speech Recognition Grammar generation. Added JSGF grammar printer.

1 files changed, 67 insertions, 0 deletions

diff --git a/src/GF/Speech/PrJSGF.hs b/src/GF/Speech/PrJSGF.hs
new file mode 100644
index 000000000..4c849e8c8
--- /dev/null
+++ b/src/GF/Speech/PrJSGF.hs
@@ -0,0 +1,67 @@
+{- 
+   **************************************************************
+    GF Module
+   
+    Description   : This module prints a CFG as a JSGF grammar.
+
+    Author        : Björn Bringert (bringert@cs.chalmers.se)
+
+    License       : GPL (GNU General Public License)
+
+    Created       : October 1, 2004
+
+    Modified      : 
+   ************************************************************** 
+-}
+
+-- FIXME: remove / warn / fail if there are int / string literal
+-- categories in the grammar
+
+-- FIXME: convert to UTF-8
+
+module PrJSGF (jsgfPrinter) where
+
+import SRG
+import Ident
+import CFGrammar
+import Parser (Symbol(..))
+import GrammarTypes
+import PrintParser
+import Option
+
+jsgfPrinter :: Ident -- ^ Grammar name
+	   -> Options -> CFGrammar -> String
+jsgfPrinter name opts cfg = prJSGF srg ""
+    where srg = makeSRG name opts cfg
+
+prJSGF :: SRG -> ShowS
+prJSGF (SRG{grammarName=name,startCat=start,origStartCat=origStart,rules=rs})
+    = header . mainCat . unlinesS (map prRule rs)
+    where
+    header = showString "#JSGF V1.0 UTF-8;" . nl 
+	     . comments ["JSGF speech recognition grammar for " ++ name,
+			 "Generated by GF"] . nl 
+	     . showString ("grammar " ++ name ++ ";") . nl
+	     . nl
+    mainCat = comments ["Start category: " ++ origStart] . nl 
+	      . showString "public <MAIN> = " . prCat start . showChar ';' . nl . nl
+    prRule (SRGRule cat origCat rhs) = 
+	comments [origCat] . nl
+        . prCat cat . showString " = " . join " | " (map prAlt rhs) . nl
+    prAlt rhs | null rhs' = showString "<NULL>"
+	      | otherwise = wrap "(" (unwordsS (map prSymbol rhs')) ")"
+		   where rhs' = rmPunct rhs
+    prSymbol (Cat c) = prCat c
+    prSymbol (Tok t) = wrap "\"" (prtS t) "\""
+    prCat c = showChar '<' . showString c . showChar '>'
+
+rmPunct :: [Symbol String Token] -> [Symbol String Token] 
+rmPunct [] = []
+rmPunct (Tok t:ss) | all isPunct (prt t) = rmPunct ss
+rmPunct (s:ss) = s : rmPunct ss
+
+isPunct :: Char -> Bool
+isPunct c = c `elem` "-_.;.,?!"
+
+comments :: [String] -> ShowS
+comments = unlinesS . map (showString . ("// " ++))