1 files changed, 181 insertions, 0 deletions
diff --git a/src/GF/Infra/Modules.hs b/src/GF/Infra/Modules.hs
new file mode 100644
index 000000000..01b789f8f
--- /dev/null
+++ b/src/GF/Infra/Modules.hs
@@ -0,0 +1,181 @@
+module Modules where
+
+import Ident
+import Option
+import Operations
+
+import List
+
+
+-- AR 29/4/2003
+
+-- The same structure will be used in both source code and canonical.
+-- The parameters tell what kind of data is involved.
+-- Invariant: modules are stored in dependency order
+
+data MGrammar i f a = MGrammar {modules :: [(i,ModInfo i f a)]}
+  deriving Show
+
+data ModInfo i f a =
+    ModMainGrammar (MainGrammar i)
+  | ModMod (Module i f a)
+  deriving Show
+
+data Module i f a = Module {
+    mtype   :: ModuleType i ,
+    flags   :: [f] ,
+    extends :: Maybe i ,
+    opens   :: [OpenSpec i] ,
+    jments  :: BinTree (i,a)
+  }
+  deriving Show
+
+-- destructive update
+
+--- dep order preserved since old cannot depend on new
+updateMGrammar :: Ord i => MGrammar i f a -> MGrammar i f a -> MGrammar i f a
+updateMGrammar old new = MGrammar $ 
+  [(i,m) | (i,m) <- os, notElem i (map fst ns)] ++ ns
+ where
+   os = modules old
+   ns = modules new
+
+updateModule :: Ord i => Module i f t -> i -> t -> Module i f t
+updateModule (Module  mt fs me ops js) i t = 
+  Module mt fs me ops (updateTree (i,t) js)
+
+data MainGrammar i = MainGrammar {
+    mainAbstract  :: i ,
+    mainConcretes :: [MainConcreteSpec i]
+  }
+  deriving Show
+
+data MainConcreteSpec i = MainConcreteSpec {
+    concretePrintname :: i ,
+    concreteName :: i ,
+    transferIn   :: Maybe (OpenSpec i) ,  -- if there is an in-transfer
+    transferOut  :: Maybe (OpenSpec i)    -- if there is an out-transfer
+  }
+  deriving Show
+
+data OpenSpec i = OSimple i | OQualif i i
+  deriving (Eq,Show)
+
+openedModule :: OpenSpec i -> i
+openedModule o = case o of
+  OSimple m -> m
+  OQualif _ m -> m
+
+-- initial dependency list
+depPathModule :: Ord i => Module i f a -> [OpenSpec i]
+depPathModule m = fors m ++ exts m ++ opens m where
+  fors m = case mtype m of
+    MTTransfer i j -> [i,j]
+    MTConcrete i   -> [OSimple i]
+    _              -> []
+  exts m = map OSimple $ maybe [] return $ extends m
+
+-- all modules that a module extends, directly or indirectly
+allExtends :: (Show i,Ord i) => MGrammar i f a -> i -> [i]
+allExtends gr i = case lookupModule gr i of
+  Ok (ModMod m) -> case extends m of 
+    Just i1 -> i : allExtends gr i1
+    _ -> [i]
+  _ -> []
+
+-- initial search path: the nonqualified dependencies
+searchPathModule :: Ord i => Module i f a -> [i]
+searchPathModule m = [i | OSimple i <- depPathModule m]
+
+-- a new module can safely be added to the end, since nothing old can depend on it
+addModule :: Ord i => 
+             MGrammar i f a -> i -> ModInfo i f a -> MGrammar i f a
+addModule gr name mi = MGrammar $ (modules gr ++ [(name,mi)])
+
+emptyMGrammar :: MGrammar i f a
+emptyMGrammar = MGrammar []
+
+
+-- we store the module type with the identifier
+
+data IdentM i = IdentM {
+  identM :: i ,
+  typeM  :: ModuleType i
+  }
+  deriving (Eq,Show)
+
+-- encoding the type of the module
+data ModuleType i = 
+    MTAbstract 
+  | MTTransfer (OpenSpec i) (OpenSpec i) 
+  | MTResource
+  | MTResourceInt
+  | MTResourceImpl i 
+  | MTConcrete i
+  | MTConcreteInt i i 
+  | MTConcreteImpl i i i
+  | MTReuse i
+  deriving (Eq,Show)
+
+typeOfModule mi = case mi of
+  ModMod m -> mtype m
+
+isResourceModule mi = case typeOfModule mi of
+  MTResource -> True
+  MTReuse _ -> True
+  MTResourceInt -> True
+  MTResourceImpl _ -> True
+  _ -> False
+
+abstractOfConcrete :: (Show i, Eq i) => MGrammar i f a -> i -> Err i
+abstractOfConcrete gr c = do
+  m <- lookupModule gr c
+  case m of
+    ModMod n -> case mtype n of
+      MTConcrete a -> return a
+      _ -> Bad $ "expected concrete" +++ show c
+    _ -> Bad $ "expected concrete" +++ show c
+
+abstractModOfConcrete :: (Show i, Eq i) => 
+                         MGrammar i f a -> i -> Err (Module i f a)
+abstractModOfConcrete gr c = do
+  a <- abstractOfConcrete gr c
+  m <- lookupModule gr a
+  case m of
+    ModMod n -> return n
+    _ -> Bad $ "expected abstract" +++ show c
+
+
+-- the canonical file name
+
+--- canonFileName s = prt s ++ ".gfc"
+
+lookupModule :: (Show i,Eq i) => MGrammar i f a -> i -> Err (ModInfo i f a)
+lookupModule gr m = case lookup m (modules gr) of
+  Just i -> return i
+  _ -> Bad $ "unknown module" +++ show m 
+             +++ "among" +++ unwords (map (show . fst) (modules gr)) ---- debug
+
+lookupModuleType :: (Show i,Eq i) => MGrammar i f a -> i -> Err (ModuleType i)
+lookupModuleType gr m = do
+  mi <- lookupModule gr m
+  return $ typeOfModule mi
+
+lookupInfo :: (Show i, Ord i) => Module i f a -> i -> Err a
+lookupInfo mo i = lookupTree show i (jments mo)
+
+isModAbs m = case mtype m of
+  MTAbstract -> True
+  _ -> False
+
+isModRes m = case mtype m of
+  MTResource -> True
+  _ -> False
+
+isModCnc m = case mtype m of
+  MTConcrete _ -> True
+  _ -> False
+
+sameMType m n = case (m,n) of
+  (MTConcrete _, MTConcrete _) -> True
+  _ -> m == n