+ rbc_print, /* print(ra) -> r -- prints, leaves on stack */
+ rbc_rgba, /* rgba(ra, rb, rc, rd) -> p */
+ rbc_hsva, /* hsva(ra, rb, rc, rd) -> p */
+ rbc_alpha, /* alpha(pa) -> r */
+ rbc_log, /* log(ra) -> r */
+ rbc_exp, /* exp(ra) -> r */
+ rbc_det, /* det(ra, rb, rc, rd) -> r */