From c158886591246a431282fa1f2d4ca98fffd8b61a Mon Sep 17 00:00:00 2001
From: Kohei Takahashi <flast@flast.jp>
Date: Sat, 29 Oct 2016 21:29:26 +0900
Subject: [PATCH] Workaround for MSVC 12 variadics bug.

---
 include/boost/fusion/support/detail/and.hpp | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/include/boost/fusion/support/detail/and.hpp b/include/boost/fusion/support/detail/and.hpp
index 8560f344..1b310dda 100644
--- a/include/boost/fusion/support/detail/and.hpp
+++ b/include/boost/fusion/support/detail/and.hpp
@@ -20,7 +20,11 @@ namespace boost { namespace fusion { namespace detail {
 
     template<typename ...T>
     struct and_impl<integral_constant<T, true>...> : true_type {};
-   
+
+    // This specialization is necessary to avoid MSVC-12 variadics bug.
+    template<bool ...Cond>
+    struct and_impl1 : and_impl<integral_constant<bool, Cond>...> {};
+
     /* fusion::detail::and_ differs from mpl::and_ in the following ways:
        - The empty set is valid and returns true
        - A single element set is valid and returns the identity
@@ -29,7 +33,7 @@ namespace boost { namespace fusion { namespace detail {
          reduces instantations when returning true; the implementation is not
          recursive. */
     template<typename ...Cond>
-    struct and_ : and_impl<integral_constant<bool, Cond::value>...> {};
+    struct and_ : and_impl1<Cond::value...> {};
 }}}
 
 #endif // FUSION_AND_07152016_1625