reintroduce the compiler API

src/compiler/api/GF/Command/Parse.hs

@@ -0,0 +1,150 @@
+module GF.Command.Parse(readCommandLine, readTransactionCommand, pCommand) where
+
+import PGF(pExpr,pIdent)
+import PGF2(BindType(..),readType,readContext)
+import GF.Infra.Ident(identS)
+import GF.Grammar.Grammar(Term(Abs))
+import GF.Grammar.Parser(runPartial,pTerm)
+import GF.Command.Abstract
+
+import Data.Char(isDigit,isSpace)
+import Control.Monad(liftM2)
+import Text.ParserCombinators.ReadP
+
+readCommandLine :: String -> Maybe CommandLine
+readCommandLine s =
+    case [x | (x,cs) <- readP_to_S pCommandLine s, all isSpace cs] of
+      [x] -> Just x
+      _   -> Nothing
+
+pCommandLine =
+  (skipSpaces >> char '-' >> char '-' >> pTheRest >> return [])   -- comment
+  <++
+  (sepBy (skipSpaces >> pPipe) (skipSpaces >> char ';'))
+
+pPipe = sepBy1 (skipSpaces >> pCommand) (skipSpaces >> char '|')
+
+pCommand = (do
+  cmd  <- pIdent <++ (char '%' >> fmap ('%':) pIdent)
+  skipSpaces
+  opts <- sepBy pOption skipSpaces
+  arg  <- if getCommandOp cmd == "cc" then pArgTerm else pArgument
+  return (Command cmd opts arg)
+  )
+    <++ (do
+  char '?'
+  skipSpaces
+  c <- pSystemCommand
+  return (Command "sp" [OFlag "command" (LStr c)] ANoArg)
+  )
+
+readTransactionCommand :: String -> Maybe TransactionCommand
+readTransactionCommand s =
+    case [x | (x,cs) <- readP_to_S pTransactionCommand s, all isSpace cs] of
+      [x] -> Just x
+      _   -> Nothing
+
+pTransactionCommand = do
+  skipSpaces
+  cmd <- pIdent
+  skipSpaces
+  opts <- sepBy pOption skipSpaces
+  skipSpaces
+  kwd <- pIdent
+  skipSpaces
+  case kwd of
+    "fun" | take 1 cmd == "c" -> do
+               f <- pIdent
+               skipSpaces
+               char ':'
+               skipSpaces
+               ty <- readS_to_P (\s -> case readType s of
+                                         Just ty -> [(ty,"")]
+                                         Nothing -> [])
+               return (CreateFun opts f ty)
+          | take 1 cmd == "d" -> do
+                f <- pIdent
+                return (DropFun opts f)
+    "cat" | take 1 cmd == "c" -> do
+               c <- pIdent
+               skipSpaces
+               ctxt <- readS_to_P (\s -> case readContext s of
+                                           Just ty -> [(ty,"")]
+                                           Nothing -> [])
+               return (CreateCat opts c ctxt)
+          | take 1 cmd == "d" -> do
+                c <- pIdent
+                return (DropCat opts c)
+    "concrete"
+          | take 1 cmd == "c" -> do
+               name <- pIdent
+               return (CreateConcrete opts name)
+          | take 1 cmd == "d" -> do
+               name <- pIdent
+               return (DropConcrete opts name)
+    "lin" | elem (take 1 cmd) ["c","a"] -> do
+               f <- pIdent
+               skipSpaces
+               args <- sepBy pIdent skipSpaces
+               skipSpaces
+               char '='
+               skipSpaces
+               t  <- readS_to_P (\s -> case runPartial pTerm s of
+                                         Right (s,t) -> [(t,s)]
+                                         _ -> [])
+               return (CreateLin opts f (foldr (Abs Explicit . identS) t args) (take 1 cmd == "a"))
+          | take 1 cmd == "d" -> do
+                f <- pIdent
+                return (DropLin opts f)
+    "lincat"
+          | take 1 cmd == "c" -> do
+               f <- pIdent
+               skipSpaces
+               char '='
+               skipSpaces
+               t  <- readS_to_P (\s -> case runPartial pTerm s of
+                                         Right (s,t) -> [(t,s)]
+                                         _ -> [])
+               return (CreateLincat opts f t)
+          | take 1 cmd == "d" -> do
+                f <- pIdent
+                return (DropLincat opts f)
+    _     -> pfail
+
+pOption = do
+  char '-'
+  flg <- pIdent
+  option (OOpt flg) (fmap (OFlag flg) (char '=' >> pValue))
+
+pValue = do
+  fmap LInt (readS_to_P reads)
+  <++
+  fmap LFlt (readS_to_P reads)
+  <++
+  fmap LStr (readS_to_P reads)
+  <++
+  fmap LStr pFilename
+
+pFilename = liftM2 (:) (satisfy isFileFirst) (munch (not . isSpace)) where
+  isFileFirst c = not (isSpace c) && not (isDigit c)
+
+pArgument =
+  option ANoArg
+    (fmap AExpr pExpr
+              <++
+    (skipSpaces >> char '%' >> fmap AMacro pIdent))
+
+pArgTerm = ATerm `fmap` readS_to_P sTerm
+  where
+    sTerm s = case runPartial pTerm s of
+                Right (s,t) -> [(t,s)]
+                _ -> []
+
+pSystemCommand =
+    (char '"' >> (manyTill (pEsc <++ get) (char '"')))
+      <++
+    pTheRest
+  where
+    pEsc = char '\\' >> get
+
+pTheRest = munch (const True)