compiler: rename trait, impl to class, instance

compiler/impl.sml → compiler/instance.sml

-structure Impl: sig
+structure Instance: sig
 
-  type impl = {
+  type instance = {
     name: string,
     alpha: Ty.ty,
     self: Ty.ty,
     binds: (string * AST.term) list
   }
 
-  val implExpr: Scan.token list -> (impl * Scan.token list) Attempt.attempt
+  val instanceExpr: Scan.token list -> (instance * Scan.token list) Attempt.attempt
 
 end = struct
 
-  type impl = {
+  type instance = {
     name: string,
     alpha: Ty.ty,
     self: Ty.ty,
@@ -32,8 +32,8 @@ end = struct
   infix 1 \/
 
 
-  fun implExpr ts = (
-    litKey "impl"                      >>
+  fun instanceExpr ts = (
+    litKey "instance"                  >>
     identifier                         >>= (fn name =>
     TyExpr.tyExpr (Scan.Keyword "for") >>= (fn alpha =>
     litKey "for"                       >>

compiler/sources.cm

@@ -18,8 +18,8 @@ Group
 
   structure ParseUtil
   structure TyExpr
-  structure Trait
-  structure Impl
+  structure Class
+  structure Instance
   structure Parse
 
   structure LetReduce
@@ -53,8 +53,8 @@ is
 
   parse-util.sml
   tyexpr.sml
-  trait.sml
-  impl.sml
+  class.sml
+  instance.sml
   parse.sml
 
   letreduce.sml