diff -r 7f1cadc3ebc1 -r 7156d6699410 src/cx/map.h
--- a/src/cx/map.h	Sat Dec 13 15:16:25 2025 +0100
+++ b/src/cx/map.h	Sat Dec 13 16:27:16 2025 +0100
@@ -183,9 +183,9 @@
      * Add or overwrite an element.
      * If the @p value is @c NULL, the implementation
      * shall only allocate memory instead of adding an existing value to the map.
-     * Returns a pointer to the allocated memory or @c NULL if allocation fails.
+     * Returns a map entry where the pointer to the key is @c NULL if allocation fails.
      */
-    void *(*put)(CxMap *map, CxHashKey key, void *value);
+    CxMapEntry (*put)(CxMap *map, CxHashKey key, void *value);
 
     /**
      * Returns an element.