1 files changed, 51 insertions, 0 deletions
diff --git a/src/expr/chain.h b/src/expr/chain.h
new file mode 100644
index 000000000..e052a2ed8
--- /dev/null
+++ b/src/expr/chain.h
@@ -0,0 +1,51 @@
+/*********************                                                        */
+/*! \file chain.h
+ ** \verbatim
+ ** Original author: Morgan Deters
+ ** 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"
+
+#ifndef __CVC4__CHAIN_H
+#define __CVC4__CHAIN_H
+
+#include "expr/kind.h"
+#include <iostream>
+
+namespace CVC4 {
+
+/** A class to represent a chained, built-in operator. */
+class CVC4_PUBLIC Chain {
+  Kind d_kind;
+public:
+  explicit Chain(Kind k) : d_kind(k) { }
+  bool operator==(const Chain& ch) const { return d_kind == ch.d_kind; }
+  bool operator!=(const Chain& ch) const { return d_kind != ch.d_kind; }
+  Kind getOperator() const { return d_kind; }
+};/* class Chain */
+
+inline std::ostream& operator<<(std::ostream& out, const Chain& ch) CVC4_PUBLIC;
+inline std::ostream& operator<<(std::ostream& out, const Chain& ch) {
+  return out << ch.getOperator();
+}
+
+struct CVC4_PUBLIC ChainHashFunction {
+  size_t operator()(const Chain& ch) const {
+    return kind::KindHashFunction()(ch.getOperator());
+  }
+};/* struct ChainHashFunction */
+
+}/* CVC4 namespace */
+
+#endif  /* __CVC4__CHAIN_H */