RosettaCodeData/Task/Calendar---for-REAL-programmers/Forth/calendar---for-real-programmers.fth
2024-03-06 22:25:12 -08:00

32 lines
1.1 KiB
Forth

: WEEKDAY ( D M Y -- U )
OVER 3 < IF SWAP 12 + SWAP 1- THEN
DUP 4 / OVER 100 / - OVER 400 / + + SWAP 1+ 13 * 5 / + + 2 - 7 MOD ;
: MDAYS ( M Y -- MSIZE MDAY )
OVER 12 = IF 31 1 2SWAP WEEKDAY NEGATE EXIT THEN
2>R 1 2R@ WEEKDAY 1 2R> SWAP 1+ SWAP WEEKDAY OVER -
7 + 7 MOD 28 + SWAP NEGATE ;
: .WEEK ( MSIZE MDAY -- MSIZE MDAY' )
7 0 DO DUP 0< IF 1+ 3 SPACES ELSE
2DUP > IF 1+ DUP 2 .R SPACE ELSE 3 SPACES THEN THEN LOOP ;
: .3MONTHS ( Y M -- )
3 0 DO ." MO TU WE TH FR SA SU " LOOP CR
3 OVER + SWAP DO I OVER MDAYS ROT LOOP DROP
6 0 DO 2ROT .WEEK 2 SPACES 2ROT .WEEK 2 SPACES 2ROT .WEEK CR LOOP
2DROP 2DROP 2DROP ;
: CAL ( Y -- )
30 SPACES ." [SNOOPY]" CR
32 SPACES DUP . CR
." JANUARY FEBRUARY MARCH" CR
DUP 1 .3MONTHS
." APRIL MAY JUNE" CR
DUP 4 .3MONTHS
." JULY AUGUST SEPTEMBER" CR
DUP 7 .3MONTHS
." OCTOBER NOVEMBER DECEMBER" CR
10 .3MONTHS ;
1969 CAL