From 8f923fa081f0702cb36681675833476c17f692ce Mon Sep 17 00:00:00 2001
From: Fan Jiang <i@fanjiang.me>
Date: Mon, 22 Jun 2020 15:18:31 -0400
Subject: [PATCH] Move away from boost

---
 gtsam/base/make_shared.h | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/gtsam/base/make_shared.h b/gtsam/base/make_shared.h
index 03de30497..966dd516d 100644
--- a/gtsam/base/make_shared.h
+++ b/gtsam/base/make_shared.h
@@ -22,21 +22,28 @@
 #include <Eigen/Core>
 
 #include <boost/make_shared.hpp>
-#include <boost/utility/enable_if.hpp>
 
+#include <type_traits>
+
+#if __cplusplus <= 201103L
+namespace gtsam {
+  template<bool B, class T = void>
+  using enable_if_t = typename std::enable_if<B, T>::type;
+}
+#endif
 
 namespace gtsam {
 
   /// Add our own `make_shared` as a layer of wrapping on `boost::make_shared`
   template<typename T, typename ... Args>
-  boost::enable_if_t<has_custom_allocator<T>::value, boost::shared_ptr<T>> make_shared(Args&&... args)
+  gtsam::enable_if_t<has_custom_allocator<T>::value, boost::shared_ptr<T>> make_shared(Args&&... args)
   {
     return boost::allocate_shared<T>(Eigen::aligned_allocator<T>(), std::forward<Args> (args)...);
   }
 
   /// Fall back to the boost version if no need for alignment
   template<typename T, typename ... Args>
-  boost::enable_if_t<!has_custom_allocator<T>::value, boost::shared_ptr<T>> make_shared(Args&&... args)
+  gtsam::enable_if_t<!has_custom_allocator<T>::value, boost::shared_ptr<T>> make_shared(Args&&... args)
   {
     return boost::make_shared<T>(std::forward<Args> (args)...);
   }