How to use "gtrace" in VScode?

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1

I have [SWI-Prolog 9.0.4] installed.
When I open swipl in vscode and type “gtrace.” in terminal, it shows:

?- gtrace.
Correct to: "trace"? no
ERROR: Unknown procedure: gtrace/0
ERROR:   However, there are definitions for:
ERROR:         trace/0
ERROR:
ERROR: In:
ERROR:   [10] gtrace
ERROR:    [9] toplevel_call(user:user:gtrace) at f:/swipl/boot/toplevel.pl:1173
   Exception: (10) gtrace ?

My operating system is Windows10

2

I do use SWI-Prolog with Windows, VSCode and use gtrace. However I do not use gtrace within VSCode I use gtrace by starting the Prolog code with SWI-Prolog from the command line to open a Prolog top level then use gtrace.

Don’t know if anyone has been able to get gtrace to work with VSCode but it has been discussed before.

3

You might get away by loading the GUI connector:

 ?- [swi('swipl-win.rc')].

No idea whether it works with VSCode. It used to only work with swipl-win.exe, but these days it works to some extend for swipl.exe as well.

5

Thanks a lot!
It works after I type [swi(‘swipl-win.rc’)]. in terminal!

6

On a Mac I get this output:

?- gtrace.
% The graphical front-end will be used for subsequent tracing
true.

[trace]  ?-

It automatically goes back to trace/0 :thinking:
It’s strange because the graphical editor works fine…any clues? (BTW I like trace/0 so it’s of no importance at all, but just to understand what’s going on…)
Thanks and congrats for the new xmas-bishop owl on the swi-prolog website :joy: :joy:

7

Not sure it does. It says it loaded the GUI tracer and is now in trace mode. Normally, the next goal should appear in the graphical debugger. I normally use

 ?- gtrace, mygoal(....).
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8

It works in this way :+1:t2: Thanks

9

BTW using for once the graphical debugger had the positive outcome that I “discovered” the Gertjan van Noord (is it a pen name which stands for you, Jan? Or is this guy a real person?) definition of the member/2 predicate. Youssou would have liked it, I guess, because it’s deterministic when it’s left with a one-element list as input. Thanks

10

Gertjan is this person: Gertjan van Noord Home Page

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