diff --git a/src/library/blast/action_result.h b/src/library/blast/action_result.h
new file mode 100644
index 000000000..0af916797
--- /dev/null
+++ b/src/library/blast/action_result.h
@@ -0,0 +1,29 @@
+/*
+Copyright (c) 2015 Microsoft Corporation. All rights reserved.
+Released under Apache 2.0 license as described in the file LICENSE.
+
+Author: Leonardo de Moura
+*/
+#pragma once
+#include "kernel/expr.h"
+
+namespace lean {
+namespace blast {
+class action_result {
+public:
+    enum kind { Failed, Solved, NewBranch };
+private:
+    kind m_kind;
+    expr m_proof;
+    action_result(bool b = true):m_kind(b ? NewBranch : Failed) {}
+    action_result(expr const & pr):m_kind(Solved), m_proof(pr) {}
+public:
+    kind get_kind() const { return m_kind; }
+    expr get_proof() const { lean_assert(m_kind == Solved); return m_proof; }
+    static action_result failed() { return action_result(false); }
+    static action_result new_branch() { return action_result(true); }
+    static action_result solved(expr const & pr) { return action_result(pr); }
+};
+
+inline bool failed(action_result const & r) { return r.get_kind() == action_result::Failed; }
+}}