Devel/GF3: experimentally putting together all functionalities for the first time

src/GF/Devel/GF3.hs

@@ -0,0 +1,44 @@
+module Main where
+
+import GF.Command.Interpreter
+import GF.Command.Importing
+import GF.Command.Commands
+import GF.GFCC.API
+
+import GF.Infra.Option ---- Haskell's option lib
+
+import System (getArgs)
+
+main :: IO ()
+main = do
+  putStrLn welcome
+  xx <- getArgs
+  env <- importInEnv emptyMultiGrammar xx
+  loop env
+  return ()
+
+loop :: CommandEnv -> IO CommandEnv
+loop env = do
+  s <- getLine
+  case words s of
+    "q":_ -> return env
+    "i":args -> do
+      env1 <- importInEnv (multigrammar env) args
+      loop env1
+    _ -> do
+      interpretCommandLine env s
+      loop env
+
+importInEnv mgr0 xx = do
+  let (opts,files) = getOptions "-" xx
+  mgr1 <- case files of
+    [] -> return mgr0
+    _  -> importGrammar mgr0 opts files
+  let env = CommandEnv mgr1 (allCommands mgr1)
+  putStrLn $ unwords $ "\nLanguages:" : languages mgr1
+  return env
+
+welcome = unlines [
+  "This is GF version 3.0 alpha.",
+  "Some things may work."
+  ]