+
+/* Loop constructors are macros of the form
+ * LOOP(v,zero,n, precomp)
+ * which work much like this one:
+ */
+#define INNER(v,zero,n, precomp) \
+ for ((v)=(zero); precomp, (v)<(n); (v)++)
+
+#define FOR_VERTEX(v,loop) \
+ loop ((v), 0, N, NOTHING)