diff --git a/README.md b/README.md
index bd3798fb..9bafdd4e 100644
--- a/README.md
+++ b/README.md
@@ -5056,18 +5056,23 @@ Default oplist for C standard types (int & float)
 
 ##### M\_CSTR\_OPLIST
 
-Default oplist for the C type const char *
+Default oplist for the C type const char *, seen as a constant string.
 
 ##### M\_POD\_OPLIST
 
 Default oplist for a structure C type without any init & clear
-prerequisites.
+prerequisites (plain old data).
 
 ##### M\_A1\_OPLIST
 
 Default oplist for a array of size 1 of a structure C type without any init & clear
 prerequisites.
 
+##### M\_EMPTY\_OPLIST
+
+Default oplist for a type that shall not be instanciated.
+Each method does nothing.
+
 ##### M\_CLASSIC\_OPLIST(name)
 
 Create the oplist with the classic operators using the pattern 'name', i.e.
diff --git a/m-core.h b/m-core.h
index 3d756705..7ccd6f4b 100644
--- a/m-core.h
+++ b/m-core.h
@@ -2187,6 +2187,16 @@ m_core_hash (const void *str, size_t length)
    CLEAR(M_NOTHING_DEFAULT), EQUAL(M_MEMCMP1_A1_DEFAULT), CMP(M_MEMCMP2_A1_DEFAULT), \
    HASH(M_HASH_A1_DEFAULT))
 
+/* Oplist for a type that does nothing and shall not be instanciated */
+#define M_EMPTY_OPLIST                                                  \
+  (INIT(M_EMPTY_DEFAULT), INIT_SET(M_EMPTY_DEFAULT),                    \
+   SET(M_EMPTY_DEFAULT), CLEAR(M_EMPTY_DEFAULT),                        \
+   INIT_MOVE(M_EMPTY_DEFAULT), MOVE(M_EMPTY_DEFAULT),                   \
+   EQUAL(M_TRUE_DEFAULT), GET_STR(M_EMPTY_DEFAULT),                     \
+   OUT_STR(M_EMPTY_DEFAULT), IN_STR(M_TRUE_DEFAULT),                    \
+   OUT_SERIAL(M_EMPTY_DEFAULT), IN_SERIAL(M_TRUE_DEFAULT),              \
+   PARSE_STR(M_TRUE_DEFAULT))
+
 /* Default oplist for C standard types (int & float).
    Implement generic out_str/in_str/parse_str/get_str function if using C11.
    Add FILE I/O if stdio.h has been included