This changeset changes the default visibility of a function/predicate body outside the module that declares it. The body is now visible across the module boundary. To contain the knowledge of the body inside the module, mark the function/predicate as 'protected'.

Semantics of 'protected':
* The definition (i.e., body) of a 'protected' function is not visible outside the defining module
* The idea is that inside the defining module, a 'protected' function may or may not be opaque. However, this will be easier to support once opaque/reveal are language primitives. Therefore, for the time being, {:opaque} is not allowed to be applied to 'protected' functions.
* In order to extend the definition of a predicate in a refinement module, the predicate must be 'protected'
* The 'protected' status of a function must be preserved in refinement modules

1 files changed, 2 insertions, 2 deletions

diff --git a/Test/dafny4/ClassRefinement.dfy b/Test/dafny4/ClassRefinement.dfy
index cff6d98f..b5ecfbfa 100644
--- a/Test/dafny4/ClassRefinement.dfy
+++ b/Test/dafny4/ClassRefinement.dfy
@@ -12,7 +12,7 @@ abstract module M0 {
   class Counter {

     ghost var N: int;

     ghost var Repr: set<object>;

-    predicate Valid()

+    protected predicate Valid()

       reads this, Repr;

     {

       this in Repr

@@ -51,7 +51,7 @@ module M1 refines M0 {
   class Counter {

     var c: Cell;

     var d: Cell;

-    predicate Valid...

+    protected predicate Valid...

     {

       c != null && c in Repr &&

       d != null && d in Repr &&