diff --git a/include/rapidjson/document.h b/include/rapidjson/document.h
index 4b2d72322..ed45136cf 100644
--- a/include/rapidjson/document.h
+++ b/include/rapidjson/document.h
@@ -255,6 +255,9 @@ class GenericMemberIterator {
 
     Iterator& operator+=(DifferenceType n) { ptr_+=n; return *this; }
     Iterator& operator-=(DifferenceType n) { ptr_-=n; return *this; }
+
+    friend Iterator operator+(DifferenceType n, const Iterator& i)  { return Iterator(n+i.ptr_); }
+    friend Iterator operator-(DifferenceType n, const Iterator& i)  { return Iterator(n-i.ptr_); }
     //@}
 
     //! @name relations