topic Re: Working with TXT files and CUSTOM parameters in GDL

Working with TXT files and CUSTOM parameters

jakubc7 — Wed, 15 Sep 2021 07:45:25 GMT

I have spent some time trying to get my object to read an external text file to draw it's parameter values.
I finally got it working and then went to add an option to have a CUSTOM parameters that user can input through the UI using A and B values.

This seems much harder to achieve that I expected. Suddenly I realise that it's not that straight forward to write my custom values without using a text file.

I tried to write something like this:
IF use_custom THEN
EXECUTE ALTERNATIVE CODE
END
ENDIF

This kind of does the trick but now because I "END" the code prior to the object reading the remaining parameters, all my USER INTERFACE code is invalid and UI disappears when use_custom = 1

Turn back use_custom = 0 and I'm good again.

Can anyone suggest a way to do what I am trying to achieve ... I am not all that happy with my use_custom command so alternatives would be much appreciated.

Object attached. Thanks for your help.

Re: Working with TXT files and CUSTOM parameters

Barry Kelly — Tue, 22 Sep 2020 09:39:25 GMT

I haven't had a look at what you are doing, but if you don't want to END the script you can always ...

GOTO 999999

And then just add a line 999999 at the end of the script (or where ever you want it to jump to).

Barry.

Re: Working with TXT files and CUSTOM parameters

jakubc7 — Wed, 23 Sep 2020 02:39:34 GMT

Thanks Berry. I couldn't get GOTO "line number" to work but I did try the GOTO "SUB" to skip code.
Turns out I had another issue which I managed to fix now.

I would normally post my own resolution but it's nothing to do with my initial query so will give it a miss.
Thanks for your help as always

Re: Working with TXT files and CUSTOM parameters

Barry Kelly — Wed, 23 Sep 2020 03:11:25 GMT

jakubc7 wrote:
I couldn't get GOTO "line number" to work

Make sure you have the correct syntax for the line number (number and colon).

GOTO 999999

!!other code here

999999:      !!skip to here

Barry.

Re: Working with TXT files and CUSTOM parameters

jakubc7 — Wed, 23 Sep 2020 03:23:03 GMT

I see, makes sense.
I thought you were literally specifying and jumping to a specific code line number.

Re: Working with TXT files and CUSTOM parameters

Lingwisyer — Fri, 25 Sep 2020 01:26:29 GMT

GOto is essentially a GOsub without the ability to return

Re: Working with TXT files and CUSTOM parameters

Peter Baksa — Mon, 28 Sep 2020 07:26:43 GMT

The need for the goto is because an END statement in the master script blocks the running of other scripts too.
Another important thing is that GDL subroutines aren't like functions in other languages: the subroutine name is just a label that can be jumped to, but it can execute without a gosub if a line-to-line execution reaches it. That's why in 2d/3d/etc scripts we have to write an END statement before the first subroutine. In a master script this has to be done differently:

code
...
goto "masterEnd"

"subroutine":
    ! only executed with gosub, can be called from other scripts too
    ...
return

"masterEnd":
! last line of master script, execution continues in other scripts

Re: Working with TXT files and CUSTOM parameters

jakubc7 — Tue, 20 Oct 2020 00:33:23 GMT

Thanks Peter. I never knew the difference between the 2 commands. Good to know that GOSUB can be called from other scripts!