diff --git a/src/vim9.h b/src/vim9.h
index 96ab40e..91ff6ca 100644
--- a/src/vim9.h
+++ b/src/vim9.h
@@ -33,6 +33,7 @@
     ISN_SOURCE,	    // source autoload script, isn_arg.number is the script ID
     ISN_INSTR,	    // instructions compiled from expression
     ISN_CONSTRUCT,  // construct an object, using contstruct_T
+    ISN_OBJ_MEMBER, // object member, index is isn_arg.number
 
     // get and set variables
     ISN_LOAD,	    // push local variable isn_arg.number