GF/src is now for 2.9, and the new sources are in src-3.0 - keep it this way until the release of GF 3

src-3.0/GF/Grammar/Values.hs

@@ -0,0 +1,109 @@
+----------------------------------------------------------------------
+-- |
+-- Module      : Values
+-- Maintainer  : AR
+-- Stability   : (stable)
+-- Portability : (portable)
+--
+-- > CVS $Date: 2005/04/21 16:22:32 $ 
+-- > CVS $Author: bringert $
+-- > CVS $Revision: 1.7 $
+--
+-- (Description of the module)
+-----------------------------------------------------------------------------
+
+module GF.Grammar.Values (-- * values used in TC type checking
+	       Exp, Val(..), Env,
+	       -- * annotated tree used in editing
+	       Tree, TrNode(..), Atom(..), Binds, Constraints, MetaSubst,
+	       -- * for TC
+	       valAbsInt, valAbsFloat, valAbsString, vType,
+	       isPredefCat,
+	       cType, cPredefAbs, cInt, cFloat, cString,
+	       eType, tree2exp, loc2treeFocus
+	      ) where
+
+import GF.Data.Operations
+import GF.Data.Zipper
+
+import GF.Grammar.Grammar
+import GF.Infra.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 Integer | AtF Double
+  deriving (Eq,Show)
+
+type Binds = [(Ident,Val)]
+type Constraints = [(Val,Val)]
+type MetaSubst = [(MetaSymb,Val)]
+
+-- for TC
+
+valAbsInt :: Val
+valAbsInt = VCn (cPredefAbs, cInt)
+
+valAbsFloat :: Val
+valAbsFloat = VCn (cPredefAbs, cFloat)
+
+valAbsString :: Val
+valAbsString = VCn (cPredefAbs, cString)
+
+vType :: Val
+vType = VType
+
+cType :: Ident
+cType = identC "Type" --- #0
+
+cPredefAbs :: Ident
+cPredefAbs = identC "PredefAbs"
+
+cInt :: Ident
+cInt = identC "Int"
+
+cFloat :: Ident
+cFloat = identC "Float"
+
+cString :: Ident
+cString = identC "String"
+
+isPredefCat :: Ident -> Bool
+isPredefCat c = elem c [cInt,cString,cFloat]
+
+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
+    AtF s -> EFloat s
+  bi' = map fst bi
+  ts' = map tree2exp ts
+
+loc2treeFocus :: Loc TrNode -> Tree
+loc2treeFocus (Loc (Tr (a,ts),p)) = 
+  loc2tree (Loc (Tr (mark a, map (mapTr nomark) ts), mapPath nomark p)) 
+ where 
+   (mark, nomark) = (\(N (a,b,c,d,_)) -> N(a,b,c,d,True), 
+                     \(N (a,b,c,d,_)) -> N(a,b,c,d,False))
+