diff --git a/src/typval.c b/src/typval.c
index 38b81e8..e89ba9e 100644
--- a/src/typval.c
+++ b/src/typval.c
@@ -1405,6 +1405,15 @@
 	    case VAR_LIST: return tv->vval.v_list == NULL;
 	    case VAR_PARTIAL: return tv->vval.v_partial == NULL;
 	    case VAR_STRING: return tv->vval.v_string == NULL;
+
+	    case VAR_NUMBER: if (!in_vim9script())
+				 return tv->vval.v_number == 0;
+			     break;
+#ifdef FEAT_FLOAT
+	    case VAR_FLOAT: if (!in_vim9script())
+				 return tv->vval.v_float == 0.0;
+			     break;
+#endif
 	    default: break;
 	}
     }