diff --git a/include/boost/json/array.hpp b/include/boost/json/array.hpp
index 016cc48ba..918dcad21 100644
--- a/include/boost/json/array.hpp
+++ b/include/boost/json/array.hpp
@@ -946,7 +946,8 @@ class array
         past-the-end iterators are also invalidated.
 
         @pre
-        `first` and `last` are not iterators into `*this`.
+        `first` and `last` are not iterators into `*this`. Elements of `init`
+        do not refer to `*this` or its elements.
 
         @par Constraints
         @code