Autonumbering discards commands in multi-command lines

Question

Autonumbering discards commands in multi-command lines

Opened this issue 2 days ago · 11 comments

Hey there,

I've got a somewhat strange behaviour with using NEXT when using Autonumbering.
(Using the current Version, 2.5.14)

For testing this out i wrote a simple snippet which should clear the screen and writes(pokes) it full with letter A, row by row.

print"{clr}"
fory=0to24:forx=0to39
poke1024+(y*40)+x,1
next:next

But the resulting code in Vice looks like this:

1 PRINT "..."
2 FORY=0TO24:FORX=0TO39
3 POKE1024+(Y*40)+X,1
4 NEXT

So it discards the second NEXT (for the Y) and therefore its prints only one Line on Screen.
If I use 3 NEXT Commands in a line then only 2 appears and so on.

Strangely enough, if i mix 2 different commands and write for example this

print"{clr}"
fory=0to24:forx=0to39
poke1024+(y*40)+x,1
next:poke53281,y
next

the NEXT disappears and only the POKE 53281 Command will remain. But, if I reverse it to

print"{clr}"
fory=0to24:forx=0to39
poke1024+(y*40)+x,1
poke53281,y:next
next

it works.

print"{clr}"
fory=0to24:forx=0to39
poke1024+(y*40)+x,1
poke53281,y:next:next

Works as well.

So, i think if a multi-command line starts with NEXT, then there's some hiccup in parsing and the rest after the first NEXT will under some cirucmstances discarded.

Michael

Answer 1 · 2025-01-03T16:22:55.000Z

Hi Michael,
thanks for the report, I'll have a look as time allows.
Roland

Answer 2 · 2025-01-03T16:41:53.000Z

Had a quick look - it really is a bug. Simple story: because it ends with a colon, the first "NEXT" is recognized as label "NEXT", which is then eliminated during code generation. It is a bug, BASIC keywords must never be handled as label...
This is easy to be fixed, hope you can wait a little bit until I find the time to do so.
Roland

Answer 3 · 2025-01-03T16:57:03.000Z

Here you can try out: https://github.com/rolandshacks/vs64/releases/latest

Answer 4 · 2025-01-03T18:36:19.000Z

Hi Roland,

thank you, it works now.
But interestingly enough, I got now this error:

/home/michael/pve/code/projects/retro/c64game/src/main.bas(2): error: undefined label 'delay'
ninja: build stopped: subcommand failed.
failed with exit code 1

The code I've tested

gosub delay
print "Start"
gosub drawmap
print "End"
end

delay:
print "testlabelstuff ... wait for me...."
return

drawmap:
print"{clr}"
fory=0to24
forx=0to39
poke1024+(y*40)+x,65
next:next
return

This error only occurs on delay label. Others, like synonyms for it (waitforme and so on) works just fine.

Greetings
Michael

Answer 5 · 2025-01-04T08:01:01.000Z

This is because "DELAY" is a defined token in simon's BASIC. Currently, the label is checked against all keywords from the original BASIC and Simon's Basic (TSB to be precise). I probably should make this more configurable in future releases...

Answer 6 · 2025-01-04T09:22:23.000Z

Oh! I've thought it could be something like that but I wasn't sure!
I know Simon's BASIC but am not very familiar with it.
Well, I'll get a list of the keywords to avoid this "error" in the future :-)

thank you for your good work 👍
Michael

Answer 7 · 2025-01-04T12:43:35.000Z

I quickly build a new version (hopefully didn't screw up) - but with that new v2.5.17 you can use the flag "--noext" in the project config ("args") to disable TSB / Simon's Basic tokens. DELAY should then work as expected...
https://github.com/rolandshacks/vs64/releases/latest

Answer 8 · 2025-01-04T13:10:20.000Z

Hi Roland,

yes, DELAY is now accepted but now another error occurs.

Testcode:

print "Start"
gosub delay
print "middle"
gosub delay
print "end"
end
delay:
fordl=1to1000:next
return

turns into:

Edit: It's independent of release- or debug-mode. I've tested in both modes.

Greetings
Michael

Answer 9 · 2025-01-04T13:12:47.000Z

All right Michael, I need to do proper work here - not just trying, sorry for the issues.
I'll have a more precise look and come back here once it works fine.
Roland

Answer 10 · 2025-01-06T16:10:41.000Z

Hi Michael,

maybe you would like to look at v2.5.18 - I found and fixed an old bug at handling plain/standard BASIC V2 code. That bug wasn't detected because before 2.5.18, Simon's BASIC was the default feature set (making the original, most used code path not very well tested). I now changed the default setting towards BASIC V2, added a flag to enable Simon's BASIC (--tsb) and tested it with a handfull of basic programs.

Thanks again for your help - further feedback would be very appreciated!
Roland

https://github.com/rolandshacks/vs64/releases/latest

Answer 11 · 2025-01-06T16:43:44.000Z

Hi Roland,

installed the new version and redefined a label to delay and it works now 👍

Michael