Add accept method (JSON_VISITOR), remove is_xxx queries, remove to_json feature.

Improve comments

json/json_boolean.e

@@ -1,8 +1,8 @@
 indexing
 	description: "JSON Truth values"
 	author: "Javier Velilla"
-	date: "$Date$"
-	revision: "$Revision$"
+	date: "2008/08/24"
+	revision: "Revision 0.1"
 
 class
 
@@ -18,7 +18,7 @@ create
 feature -- Initialization
 
 	make_boolean (an_item: BOOLEAN) is
-			--
+			--Initialize.
 		do
 			item := an_item
 		end
@@ -26,19 +26,24 @@ feature -- Initialization
 feature -- Access
 
 	item: BOOLEAN
+		-- Content
 
-	to_json: STRING is
-			--
-		do
-			Result := item.out
-		end
 
 	hash_code: INTEGER is
-			--
+			--Hash code value
 		do
 			Result := item.hash_code
 		end
 
+feature -- Visitor pattern
+
+	accept (a_visitor: JSON_VISITOR) is
+			-- Accept `a_visitor'.
+			-- (Call `visit_json_boolean' procedure on `a_visitor'.)
+		do
+			a_visitor.visit_json_boolean (Current)
+		end
+
 
 
 end