MY-BASIC

[Cybermonkey342]

@Wang: I used the actual Github sources and ran into a problem ...
The following (part of the) program gives an error:

Code: [Select]

...
do
 cls
 x(i)=mousex
 y(i)=mousey
 gosub draw
 i=i+1
 if i>=1000 then i=i-1000
 sync

until keypressed=true
end

draw:
...
return

The error occurs in the line of the until statement:

Error: Line 23, Column 5: Wrong function reached in file _core_until

Any idea? Until I compiled it with the new sources it worked fine.

[John]

Maybe doing a DIF of the two would shed some light.

[Cybermonkey342]

It also seems that the exit function does'nt work properly anymore. The following code does not draw a mandelbrot with the actual my-basic.c and .h files.
I am using now the older  ones which work fine. I hope you can fix that issues soon.

Code: Text

1. screen (256,256,"Fractal")
2.  
3. bx=0
4. by=0
5. bw=256*1
6. bh=256*1
7.  
8. sx=-2.2
9. sy=-1.7
10. sw=3.4
11. sh=3.4
12.  
13. cls
14. time1=tickcount
15. for x=bx to bx+bw
16.  for y=by to by+bh
17.    gx=(x-bx)/bw*sw+sx
18.    gy=(y-by)/bh*sh+sy
19.    zx=gx
20.    zy=gy
21.    for c=0 to 255
22.     col = c
23.     nzx=zx*zx - zy*zy + gx
24.     zy=2*zx*zy+gy
25.     zx=nzx
26.     if zx*zx + zy*zy > 4 then  col = c:  exit
27.   next
28.   r = col*256+col*32*0.5
29.   v = col*256+col*64*0.5
30.   b = col*256+col*32*0.8      
31.   ink (r,v,b)
32.   pset (x,y)
33.  next
34.  redraw
35. next
36. time2=tickcount
37. ink (255,255,255)
38. time=(time2-time1)/1000
39. drawtext (0,0,"Time needed: "+str (time)+" seconds")
40. sync
41. inkey

[wangrenxin]

Marcus, which revision is the well worked one? I'd check it as soon as possible, but it's not easy to find a debug enviroument during Chinese new year.

EDIT: I finally get a debugger, try the latest revision. I fixed the wrong function error, and the EXIT issue; but there's still an issue with the EXIT statement and multiple line IF statement, I'll check it later seriously.

[Cybermonkey342]

Thanks, and a Happy Chinese New Year. (新年好  )

[wangrenxin]

 

I've fixed the EXIT bug with multiple line IF.

[John]

Thanks Wang!

I'll give it a try from the embedding standpoint and 64 bit Linux.

Curious. Would you have an interest in contributing to the C BASIC project with your C skills? Maybe converting MyBASIC source to C BASIC could act as a tutorial and make the code easier to read. Even if you have no interest in a make-over, your input would be appreciated if you have time.

[wangrenxin]

Thank you for inviting me, John. But I'm affraid it's difficult for me to dedicate to more hobby projects now. The CB forums looks interesting, I'll join and take a look around.

[John]

C BASIC is a fun project and not really a language. It's a preprocessor helper tool to make C look more like BASIC.

[Cybermonkey342]

I've fixed the EXIT bug with multiple line IF.

Sorry, but it still doesn't work as expected. I think the problem lies in line 26 of the above fractal example:

Code: [Select]

    if zx*zx + zy*zy > 4 then col = c:  exitThis only works with the older my-basic files. If I change the line into

Code: [Select]

if zx*zx + zy*zy > 4 then
 col = c
exit
endifit even does not work with that older revision.

[John]

Is it just EXIT or any compound statement after a THEN?

[wangrenxin]

Markus, please check the latest revision.

[John]

Hi Wang,

Here is my quick test.

Code: [Select]

DECLARE SUB mb_init ALIAS "mbas_init" LIB "mb"
DECLARE SUB mb_dispose ALIAS "mbas_dispose" LIB "mb"
DECLARE SUB mb_open ALIAS "mbas_open" LIB "mb"
DECLARE SUB mb_close ALIAS "mbas_close" LIB "mb"
DECLARE SUB mb_load_str ALIAS "mbas_load_str" LIB "mb"
DECLARE SUB mb_run ALIAS "mbas_run" LIB "mb"

mb_code = """
x = 10 : y = 2 : z = 30

IF x = 1 THEN PRINT "One"; : GOTO Done
IF y = 2 THEN PRINT "Two"; : GOTO Done
IF z = 3 THEN PRINT "Three"; : GOTO Done

Done:

END
"""
mb_init()
mb_open()
mb_load_str(mb_code)
mb_run()
mb_close()
mb_dispose()


jrs@laptop:~/sb/sb22/mybasic$ scriba testmbthen.sb
Two
jrs@laptop:~/sb/sb22/mybasic$

[Cybermonkey342]

Markus, please check the latest revision.

Yes, thanks it works now.
Although there's another issue now. If I check if the window was closed MY-BASIC now doesn't end the program anymore.
This does not work:

Code: [Select]

if windowclosed = true then
 end
endifHowever, any other function (e.g. exit) is exceuted ...

[wangrenxin]

If I check if the window was closed MY-BASIC now doesn't end the program anymore.

The TRUE is defined as integer 1 and FALSE as integer 0 in MY-BASIC, that means 1 equals to true, but 2 not equals to true nor equals to false. It won't execute the END statement if windowclosed doesn't equal to 1. Currently, it's able to use following ways to test a condition steady.

1.

Code: Visual Basic

1. if windowclosed <> false then
2.  end
3. endif
4.  

2.

Code: Visual Basic

1. if windowclosed then
2.  end
3. endif
4.  

I would dismiss this confusion in later refactoring.