diff -r 380bd45bc94a -r 2dd841e364af src/cx/map.h
--- a/src/cx/map.h	Mon Apr 17 21:47:34 2023 +0200
+++ b/src/cx/map.h	Tue Apr 18 18:01:41 2023 +0200
@@ -56,21 +56,9 @@
 
 /** Structure for the UCX map. */
 struct cx_map_s {
+    CX_COLLECTION_MEMBERS
     /** The map class definition. */
     cx_map_class *cl;
-    /** An allocator that is used for the map elements. */
-    CxAllocator *allocator;
-    /** The number of elements currently stored. */
-    size_t size;
-    /**
-     * The size of an element.
-     */
-    size_t item_size;
-    /**
-     * True, if this map shall store pointers instead
-     * of copies of objects.
-     */
-    bool store_pointers;
 };
 
 /**
@@ -179,7 +167,7 @@
  */
 __attribute__((__nonnull__))
 static inline void cxMapStoreObjects(CxMap *map) {
-    map->store_pointers = false;
+    map->store_pointer = false;
 }
 
 /**
@@ -196,7 +184,7 @@
  */
 __attribute__((__nonnull__))
 static inline void cxMapStorePointers(CxMap *map) {
-    map->store_pointers = true;
+    map->store_pointer = true;
     map->item_size = sizeof(void *);
 }