; Enumerate constants

MACRO? const_def
	if _NARG >= 1
		DEF const_value = \1
	else
		DEF const_value = 0
	endc
	if _NARG >= 2
		DEF const_inc = \2
	else
		DEF const_inc = 1
	endc
ENDM

MACRO? const
	DEF \1 EQU const_value
	DEF const_value += const_inc
ENDM

MACRO? shift_const
	DEF \1 EQU 1 << const_value
	const \1_F
ENDM

MACRO? const_skip
	if _NARG >= 1
		DEF const_value += const_inc * (\1)
	else
		DEF const_value += const_inc
	endc
ENDM

MACRO? const_next
	if (const_value > 0 && \1 < const_value) || (const_value < 0 && \1 > const_value)
		fail "const_next cannot go backwards from {const_value} to \1"
	else
		DEF const_value = \1
	endc
ENDM

MACRO? rb_skip
	if _NARG == 1
		rsset _RS + \1
	else
		rsset _RS + 1
	endc
ENDM