handle unknowns words graciously in parseAny

src/GF/API.hs

@@ -109,7 +109,8 @@ parse :: GFGrammar -> GFCat -> String -> [Tree]
 parse sgr cat = errVal [] . parseString noOptions sgr cat
 
 parseAny :: [GFGrammar] -> GFCat -> String -> [Tree]
-parseAny grs cat s = concat [parse gr cat s | gr <- grs]
+parseAny grs cat s = 
+  concat [errVal [] (parseString (options [iOpt "trynextlang"]) gr cat s) | gr <- grs]
 
 translate :: GFGrammar -> GFGrammar -> GFCat -> String -> [String]
 translate ig og cat = map (linearize og) . parse ig cat
@@ -121,7 +122,8 @@ translateFromAny :: [GFGrammar] -> GFGrammar -> GFCat -> String -> [String]
 translateFromAny igs og cat s = concat [translate ig og cat s | ig <- igs]
 
 translateBetweenAll :: [GFGrammar] -> GFCat -> String -> [String]
-translateBetweenAll grs cat = concat . map (linearizeToAll grs) . parseAny grs cat
+translateBetweenAll grs cat = 
+  concat . map (linearizeToAll grs) . parseAny grs cat
 
 homonyms :: GFGrammar -> GFCat -> Tree -> [Tree]
 homonyms gr cat = nub . parse gr cat . linearize gr

src/GF/UseGrammar/Parsing.hs

@@ -52,8 +52,9 @@ parseString os sg cat = liftM fst . parseStringMsg os sg cat
 
 parseStringMsg :: Options -> StateGrammar -> CFCat -> String -> Err ([Tree],String)
 parseStringMsg os sg cat s = do
-  (ts,(_,ss)) <- checkStart $ parseStringC os sg cat s
-  return (ts, unlines $ reverse ss)
+  case checkStart $ parseStringC os sg cat s of
+    Ok (ts,(_,ss)) -> return (ts, unlines $ reverse ss)
+    Bad s -> return ([],s)
 
 parseStringC :: Options -> StateGrammar -> CFCat -> String -> Check [Tree]
 parseStringC opts0 sg cat s 
@@ -92,7 +93,8 @@ parseStringC opts0 sg cat s
         uncap s = s
 
   case unknowns of
-    _:_ -> fail $ "Unknown words:" +++ unwords unknowns
+    _:_ | oElem (iOpt "trynextlang") opts -> return []
+    _:_  -> fail $ "Unknown words:" +++ unwords unknowns
     _ -> do  
   
      ts <- checkErr $ New.parse algorithm strategy (pInfo sg) (absId sg) cat toks