+#define OFFSET(a) ((int) ((uint8_t *) (a) - ao_lisp_const))
+
+#if 0
+static int cons_depth;
+#define DBG(...) do { int d; for (d = 0; d < cons_depth; d++) printf (" "); printf(__VA_ARGS__); } while(0)
+#define DBG_IN() (cons_depth++)
+#define DBG_OUT() (cons_depth--)
+#define DBG_PR(c) ao_lisp_cons_print(ao_lisp_cons_poly(c))
+#define DBG_PRP(p) ao_lisp_poly_print(p)
+#else
+#define DBG(...)
+#define DBG_IN()
+#define DBG_OUT()
+#define DBG_PR(c)
+#define DBG_PRP(p)
+#endif
+