1- Changed LieScalar class so it is derived from "DerivedValues".

2- Added an include guard to Values-inl.h.

gtsam/base/LieScalar.h

@@ -17,6 +17,7 @@
 
 #pragma once
 
+#include <gtsam/base/DerivedValue.h>
 #include <gtsam/base/Lie.h>
 
 namespace gtsam {
@@ -24,7 +25,7 @@ namespace gtsam {
 	/**
 	 * LieScalar is a wrapper around double to allow it to be a Lie type
 	 */
-	struct LieScalar {
+	struct LieScalar : public DerivedValue<LieScalar> {
 
 		/** default constructor */
 		LieScalar() : d_(0.0) {}

gtsam/nonlinear/Values-inl.h

@@ -22,6 +22,8 @@
  *  which is also a manifold element, and hence supports operations dim, retract, and localCoordinates.
  */
 
+#pragma once
+
 #include <utility>
 #include <boost/type_traits/conditional.hpp>
 #include <boost/type_traits/is_base_of.hpp>