add new theory (sets)

Specification (smt2) -- as per this commit, subject to change

- Parameterized sort Set, e.g. (Set Int)

- Empty set constant (typed), use with "as" to specify the type, e.g.
    (as emptyset (Set Int))

- Create a singleton set
    (setenum X (Set X)) : creates singleton set

- Functions/operators
    (union (Set X) (Set X) (Set X))
    (intersection (Set X) (Set X) (Set X))
    (setminus (Set X) (Set X) (Set X))

- Predicates
    (in X (Set X) Bool) : membership
    (subseteq (Set X) (Set X) Bool) : set containment

1 files changed, 4 insertions, 0 deletions

diff --git a/src/context/cdhashset.h b/src/context/cdhashset.h
index e2ffac49b..881c3f629 100644
--- a/src/context/cdhashset.h
+++ b/src/context/cdhashset.h
@@ -57,6 +57,10 @@ public:
     return super::size();
   }
 
+  bool empty() const {
+    return super::empty();
+  }
+
   bool insert(const V& v) {
     return super::insert_safe(v, true);
   }