From 8765ee198373eb3effa3c2a91860519e30cdd16e Mon Sep 17 00:00:00 2001
From: Peter Dimov <pdimov@pdimov.com>
Date: Sat, 3 Jun 2017 00:12:01 +0300
Subject: [PATCH] Add expected::operator>> as an alias for .then

---
 include/boost/variant2/expected.hpp | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/include/boost/variant2/expected.hpp b/include/boost/variant2/expected.hpp
index d2b6581..e490625 100644
--- a/include/boost/variant2/expected.hpp
+++ b/include/boost/variant2/expected.hpp
@@ -409,6 +409,18 @@ public:
             return unexpected();
         }
     }
+
+    template<class F> then_result<F, T const&> operator>>( F && f ) const
+    {
+        if( has_value() )
+        {
+            return std::forward<F>(f)( **this );
+        }
+        else
+        {
+            return unexpected();
+        }
+    }
 };
 
 template<class T, class... E> inline constexpr bool operator==( expected<T, E...> const & x1, expected<T, E...> const & x2 )