date_formatting.yasm

#define day        a
#define month      b
#define n10        c
#define suffix     d
#define sfx_rd	   e

#define offset_jan f
#define offset_feb g
#define offset_mar h
#define offset_apr i
#define offset_may j
#define offset_jun k
#define offset_jul l
#define offset_aug m
#define offset_sep n
#define offset_oct o
#define offset_nov p
#define offset_dec q

#define sfx_th	   r
#define special	   s
#define sfx_nd	   t

#import lib.yasm

#define handle_offset(Offset, Name) {
	day-=Offset
	month=Name
	gotosubmit
}

@init_constants:
	offset_jan=30
	offset_feb=58
	offset_mar=89
	offset_apr=119
	offset_may=150
	offset_jun=180
	offset_jul=211
	offset_aug=242
	offset_sep=272
	offset_oct=303
	offset_nov=333
	sfx_rd="rd"
	sfx_th="th"
	sfx_nd="nd"

@start:
	day=:a;
	goto
		label_jan
		+(day>offset_jan)
		+(day>offset_feb)
		+(day>offset_mar)
		+(day>offset_apr)
		+(day>offset_may)
		+(day>offset_jun)
		+(day>offset_jul)
		+(day>offset_aug)
		+(day>offset_sep)
		+(day>offset_oct)

@submit:
	n10=day%10
	special=(n10<2)+"st"
		+(n10==2)+sfx_nd
		+(n10==3)+sfx_rd
		+(n10>3)+sfx_th
		-"0st"
		-(0+sfx_nd)
		-(0+sfx_rd)
		-(0+r)
		-1
	
@final:
	suffix=special;
	if n10<1or(day>9andday<14)then
		suffix=r;
	end

	:o=day+suffix+" "+month
	:done=1
	gotostart

@label_jan:
	day=day+1
	month="Jan"
	gotosubmit

@label_feb:
	handle_offset(30, "Feb")

@label_mar:
	handle_offset(58, "Mar")

@label_apr:
	handle_offset(89, "Apr")

@label_may:
	handle_offset(119, "May")

@label_jun:
	handle_offset(150, "Jun")

@label_jul:
	handle_offset(180, "Jul")

@label_aug:
	handle_offset(211, "Aug")

@label_sept:
	handle_offset(242, "Sep")

@label_oct:
	handle_offset(272, "Oct")

@label_nov:
	ifday>333then
		day-=333
		month="Dec"
	else;
		day-=303
		month="Nov"
	end
	gotosubmit