1 files changed, 72 insertions, 0 deletions
diff --git a/src/expr/sepconst.h b/src/expr/sepconst.h
new file mode 100644
index 000000000..9f86c7efc
--- /dev/null
+++ b/src/expr/sepconst.h
@@ -0,0 +1,72 @@
+/*********************                                                        */
+/*! \file sepconst.h
+ ** \verbatim
+ ** Original author: Andrew Reynolds
+ ** Major contributors: none
+ ** Minor contributors (to current version): none
+ ** This file is part of the CVC4 project.
+ ** Copyright (c) 2009-2014  New York University and The University of Iowa
+ ** See the file COPYING in the top-level source directory for licensing
+ ** information.\endverbatim
+ **
+ ** \brief [[ Add one-line brief description here ]]
+ **
+ ** [[ Add lengthier description here ]]
+ ** \todo document this file
+ **/
+
+#include "cvc4_public.h"
+
+#pragma once
+
+namespace CVC4 {
+  // messy; Expr needs NilRef (because it's the payload of a
+  // CONSTANT-kinded expression), and NilRef needs Expr.
+  class CVC4_PUBLIC NilRef;
+  //class CVC4_PUBLIC EmpStar;
+}/* CVC4 namespace */
+
+#include "expr/expr.h"
+#include "expr/type.h"
+#include <iostream>
+
+namespace CVC4 {
+
+class CVC4_PUBLIC NilRef {
+  const Type d_type;
+  NilRef() { }
+public:
+  NilRef(Type refType):d_type(refType) { }
+
+  ~NilRef() throw() {
+  }
+  Type getType() const { return d_type; }
+  bool operator==(const NilRef& es) const throw() {
+    return d_type == es.d_type;
+  }
+  bool operator!=(const NilRef& es) const throw() {
+    return !(*this == es);
+  }
+  bool operator<(const NilRef& es) const throw() {
+    return d_type < es.d_type;
+  }
+  bool operator<=(const NilRef& es) const throw() {
+    return d_type <= es.d_type;
+  }
+  bool operator>(const NilRef& es) const throw() {
+    return !(*this <= es);
+  }
+  bool operator>=(const NilRef& es) const throw() {
+    return !(*this < es);
+  }
+};/* class NilRef */
+
+std::ostream& operator<<(std::ostream& out, const NilRef& es) CVC4_PUBLIC;
+
+struct CVC4_PUBLIC NilRefHashFunction {
+  inline size_t operator()(const NilRef& es) const {
+    return TypeHashFunction()(es.getType());
+  }
+};/* struct NilRefHashFunction */
+
+}/* CVC4 namespace */