Code Golfing in Commodore BASIC

Post by wazoox » Tue, Oct 03, 2023, 10:56 AM UTC

unwind wrote: post #38

elvis70 wrote: post #31

Earlier quoted context omitted.

Not the GP but you can find it on the "HEBDOGICIEL, les listings" Website [1]. Deulignes section, page 15 [2] (Casse-briques by Laurent Auble). Published in issue 104, page 12 (second box) [3]: 1 SPRITEON:IFK=2THENR=-2:B=2*SGN(X-Z-4):RETURNELSEIFK=0THENCOLOR4,0,0:SCREEN2,1:DEFINTA-Z:J=186:X=140:Y=80:VPOKE14336,128:VPOKE14344,248:LINE(80,40)-(183,61),7,BF:LINE(78,7)-(184,J),2,B:LINE(Y,8)-(183,10),1,BF:R=2:B=2:Z=X:ONSP…

Great find, thanks! It didn't seem like any of your links was to a playable version, so I had a Goog' and a paste and came up with [1]. Pretty impressive game for that amount of code, I'd say. I've never written a line of code on an actual MSX machine (even though I was around in the 80s), it's kind of amazing the amount of emulation Magic Power we casually throw around, these days. Massive thanks to all the emulatio…

I remember this one well because I had an MSX, and like everyone else back then I didn't have that many games to play with, so I used this code quite extensively :)

Post by pgeorgi » Thu, Oct 05, 2023, 7:48 PM UTC

dep_b wrote: post #39

vidarh wrote: post #17

Earlier quoted context omitted.

The BASIC code is only in it's full textual form on screen. The moment you press return on it, it's tokenized, and it's stored tokenized both in memory and when saved. Unlike modern systems, the full textual representation of the code is never stored anywhere.

When I SAVE a program in C64 BASIC and LOAD it again the syntax doesn't change no matter what I do, add spaces or not, use shorthand or not, colons, etcetera. So I get the feeling that my whole program gets saved as a string and then parsed, not tokenized and saved. Also there is a line limit in C64 BASIC that would overflow if certain shorthand would be expanded and for beginners to see their fully written keywords…

The keywords are tokenized, the line number is converted to a 16bit integer, leading spaces are stripped (which is why some "formatted" BASIC uses ":" as the first character in a line, like the following), everything else is kept intact.

10 for i = 1 to 10

20 : (arbitrary number of spaces) print "hello"

30 next

The short hand issue is real, too:

1?:?:?:?:?:?:?:?:?:?:?:?:?:?:?:?:?:?:?:?:?:?:?:?:?:?:?:?:?:?:?:?:?:?:?:?:?:?:?:?

expands into six lines of "1 print:print:....:print" that you can't simply edit because the limit is 80 characters (two lines)

Re: Code Golfing in Commodore BASIC

Re: Code Golfing in Commodore BASIC