X-Git-Url: https://git.distorted.org.uk/~mdw/sod/blobdiff_plain/267dd3e78997ba6f5a0801c0afab2148dd049f16..c2438e62e7c3cf1b7006522cef61e8c6f797600b:/lib/sod.h?ds=sidebyside

diff --git a/lib/sod.h b/lib/sod.h
index 919b927..8270895 100644
--- a/lib/sod.h
+++ b/lib/sod.h
@@ -53,7 +53,7 @@ struct sod_vtable {
  * these.
  */
 struct sod_instance {
-  struct sod_vtable *_vt;		/* Pointer to (chain's) vtable */
+  const struct sod_vtable *_vt;		/* Pointer to (chain's) vtable */
 };
 
 /* Information about a particular chain of superclasses.  In each class,
@@ -124,6 +124,18 @@ struct sod_chain {
   ((struct cls##__ilayout *)						\
    ((char *)(obj) - offsetof(struct cls##__ilayout, chead)))
 
+/* --- @SOD__CAR@ --- *
+ *
+ * Arguments:	@...@ = a nonempty list of arguments
+ *
+ * Returns:	The first argument only.
+ */
+
+#if __STDC_VERSION__ >= 199901
+#  define SOD__CAR(...) SOD__CARx(__VA_LIST__, _)
+#  define SOD__CARx(a, ...) a
+#endif
+
 /*----- Utility macros ----------------------------------------------------*/
 
 /* --- @SOD_CLASSOF@ --- *