From d7c8a569ac572775e362ca8e6ba99586f8e16ea0 Mon Sep 17 00:00:00 2001
From: Simon Brand <tartanllama@gmail.com>
Date: Tue, 19 Dec 2017 15:23:56 +0000
Subject: [PATCH] Constexpr fixes

---
 tl/expected.hpp | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/tl/expected.hpp b/tl/expected.hpp
index 6515668..c88f7fa 100644
--- a/tl/expected.hpp
+++ b/tl/expected.hpp
@@ -78,6 +78,12 @@
 #define TL_EXPECTED_GCC49_CONSTEXPR constexpr
 #endif
 
+#ifdef TL_EXPECTED_MSVC2015_CONSTEXPR
+#define TL_EXPECTED_MSVC2015_CONSTEXPR
+#else
+#define TL_EXPECTED_MSVC2015_CONSTEXPR constexpr
+#endif
+
 #if (__cplusplus == 201103L || defined(TL_EXPECTED_MSVC2015) ||                \
      defined(TL_EXPECTED_GCC49)) &&                                            \
     !defined(TL_EXPECTED_GCC54)
@@ -1380,7 +1386,7 @@ public:
       class U = T,
       detail::enable_if_t<!std::is_convertible<U &&, T>::value> * = nullptr,
       detail::expected_enable_forward_value<T, E, U> * = nullptr>
-  explicit constexpr expected(U &&v) : expected(in_place, std::forward<U>(v)) {}
+  explicit TL_EXPECTED_MSVC2015_CONSTEXPR expected(U &&v) : expected(in_place, std::forward<U>(v)) {}
 
   /// \exclude
   template <