Founding the newly structured GF2.0 cvs archive.

src/GF/Grammar/Values.hs

@@ -0,0 +1,52 @@
+module Values where
+
+import Operations
+import Zipper
+
+import Grammar
+import Ident
+
+-- values used in TC type checking
+
+type Exp = Term
+
+data Val = VGen Int Ident | VApp Val Val | VCn QIdent | VType | VClos Env Exp 
+  deriving (Eq,Show)
+
+type Env = [(Ident,Val)]
+
+-- annotated tree used in editing
+
+type Tree = Tr TrNode
+
+newtype TrNode = N (Binds,Atom,Val,(Constraints,MetaSubst),Bool) 
+  deriving (Eq,Show)
+
+data Atom = AtC Fun | AtM MetaSymb | AtV Ident | AtL String | AtI Int
+  deriving (Eq,Show)
+
+type Binds = [(Ident,Val)]
+type Constraints = [(Val,Val)]
+type MetaSubst = [(MetaSymb,Val)]
+
+-- for TC
+
+vType :: Val
+vType = VType
+
+cType :: Ident
+cType = identC "Type" --- #0
+
+eType :: Exp
+eType = Sort "Type"
+
+tree2exp :: Tree -> Exp
+tree2exp (Tr (N (bi,at,_,_,_),ts)) = foldr Abs (foldl App at' ts') bi' where
+  at' = case at of
+    AtC (m,c) -> Q m c
+    AtV i -> Vr i
+    AtM m -> Meta m
+    AtL s -> K s
+    AtI s -> EInt s
+  bi' = map fst bi
+  ts' = map tree2exp ts