Merge in trunk changes from r758432:768028cmake

git-svn-id: https://svn.apache.org/repos/asf/qpid/branches/cmake@768053 13f79535-47bb-0310-9956-ffa450edef68

1 files changed, 8 insertions, 3 deletions

diff --git a/qpid/cpp/src/qpid/client/Handle.h b/qpid/cpp/src/qpid/client/Handle.h
index d8b822d0f9..12fb4cf3c1 100644
--- a/qpid/cpp/src/qpid/client/Handle.h
+++ b/qpid/cpp/src/qpid/client/Handle.h
@@ -30,9 +30,11 @@ namespace client {
 template <class T> class HandlePrivate;
 
 /**
- * A handle is like a pointer: it points to some underlying object.
+ * A handle is like a pointer: it points to some implementation object.
+ * Copying the handle does not copy the object.
+ * 
  * Handles can be null,  like a 0 pointer. Use isValid(), isNull() or the
- * implicit conversion to bool to test for a null handle.
+ * conversion to bool to test for a null handle.
  */
 template <class T> class Handle {
   public:
@@ -46,8 +48,11 @@ template <class T> class Handle {
     /**@return true if handle is null. It is an error to call any function on a null handle. */
     QPID_CLIENT_EXTERN bool isNull() const { return !impl; }
 
+    /** Conversion to bool supports idiom if (handle) { handle->... } */
     QPID_CLIENT_EXTERN operator bool() const { return impl; }
-    QPID_CLIENT_EXTERN bool operator !() const { return impl; }
+
+    /** Operator ! supports idiom if (!handle) { do_if_handle_is_null(); } */
+    QPID_CLIENT_EXTERN bool operator !() const { return !impl; }
 
     QPID_CLIENT_EXTERN void swap(Handle<T>&);