diff --git a/include/boost/coroutine2/detail/pull_coroutine.hpp b/include/boost/coroutine2/detail/pull_coroutine.hpp
index 32cd68e..928a477 100644
--- a/include/boost/coroutine2/detail/pull_coroutine.hpp
+++ b/include/boost/coroutine2/detail/pull_coroutine.hpp
@@ -56,8 +56,7 @@ public:
 
     pull_coroutine & operator=( pull_coroutine && other) noexcept {
         if ( this == & other) return * this;
-        cb_ = other.cb_;
-        other.cb_ = nullptr;
+        std::swap( cb_, other.cb_);
         return * this;
     }
 
@@ -168,8 +167,7 @@ public:
 
     pull_coroutine & operator=( pull_coroutine && other) noexcept {
         if ( this == & other) return * this;
-        cb_ = other.cb_;
-        other.cb_ = nullptr;
+        std::swap( cb_, other.cb_);
         return * this;
     }
 
@@ -278,8 +276,7 @@ public:
 
     pull_coroutine & operator=( pull_coroutine && other) noexcept {
         if ( this == & other) return * this;
-        cb_ = other.cb_;
-        other.cb_ = nullptr;
+        std::swap( cb_, other.cb_);
         return * this;
     }
 
diff --git a/include/boost/coroutine2/detail/push_coroutine.hpp b/include/boost/coroutine2/detail/push_coroutine.hpp
index d152be2..e68c880 100644
--- a/include/boost/coroutine2/detail/push_coroutine.hpp
+++ b/include/boost/coroutine2/detail/push_coroutine.hpp
@@ -54,8 +54,7 @@ public:
 
     push_coroutine & operator=( push_coroutine && other) noexcept {
         if ( this == & other) return * this;
-        cb_ = other.cb_;
-        other.cb_ = nullptr;
+        std::swap( cb_, other.cb_);
         return * this;
     }
 
@@ -134,8 +133,7 @@ public:
 
     push_coroutine & operator=( push_coroutine && other) noexcept {
         if ( this == & other) return * this;
-        cb_ = other.cb_;
-        other.cb_ = nullptr;
+        std::swap( cb_, other.cb_);
         return * this;
     }
 
@@ -212,8 +210,7 @@ public:
 
     push_coroutine & operator=( push_coroutine && other) noexcept {
         if ( this == & other) return * this;
-        cb_ = other.cb_;
-        other.cb_ = nullptr;
+        std::swap( cb_, other.cb_);
         return * this;
     }