Numbas Error: Error loading question 4: Variable s is not defined.

[Ben Brawn]

Hi Christian, 

We have a exam which is a scorm object on canvas. We have had some users report this error on Firefox. I've reproduced the error on Firefox. The error occurs when you reload the page using F5 etc. The exam is https://numbas.mathcentre.ac.uk/exam/39979/marq-7-unlocked-maths-awareness-and-readiness-quiz/ 

Anything we can do or look into?

Thanks

Ben

Numbas Error: Error loading question 4: Variable s is not defined.

Numbas.Error@https://syd.scorm.canvaslms.com/courses/sconeID/scone_prod.sha256_6debe94584c1108bfa6827085405eddf3bf376e7d5f6d2c896a8cc6cf8de5a8c/0/scripts.js?build_time=1752205647.3423:75:13
loadQuestion@https://syd.scorm.canvaslms.com/courses/sconeID/scone_prod.sha256_6debe94584c1108bfa6827085405eddf3bf376e7d5f6d2c896a8cc6cf8de5a8c/0/scripts.js?build_time=1752205647.3423:40222:19
Numbas.store[method_name]@https://syd.scorm.canvaslms.com/courses/sconeID/scone_prod.sha256_6debe94584c1108bfa6827085405eddf3bf376e7d5f6d2c896a8cc6cf8de5a8c/0/scripts.js?build_time=1752205647.3423:41745:48
resume/<@https://syd.scorm.canvaslms.com/courses/sconeID/scone_prod.sha256_6debe94584c1108bfa6827085405eddf3bf376e7d5f6d2c896a8cc6cf8de5a8c/0/scripts.js?build_time=1752205647.3423:38996:32
on/promise on/promise<@https://syd.scorm.canvaslms.com/courses/sconeID/scone_prod.sha256_6debe94584c1108bfa6827085405eddf3bf376e7d5f6d2c896a8cc6cf8de5a8c/0/scripts.js?build_time=1752205647.3423:39725:24

[Ben Brawn]

The other thing I noticed is that a different version of the quiz gets a different variable (in this case, x) the quizzes have the same questions in the same order, the quizzes are just put together differently
https://numbas.mathcentre.ac.uk/exam/39978/marq-7-maths-awareness-and-readiness-quiz/ 

Numbas Error: Error loading question 4: Variable x is not defined.

Numbas.Error@https://syd.scorm.canvaslms.com/courses/sconeID/scone_prod.sha256_2a60b51e63de910afc54993a0ec5fe90ad8151200843f8d6aaed4212c71da175/0/scripts.js?build_time=1752205624.915858:75:13
loadQuestion@https://syd.scorm.canvaslms.com/courses/sconeID/scone_prod.sha256_2a60b51e63de910afc54993a0ec5fe90ad8151200843f8d6aaed4212c71da175/0/scripts.js?build_time=1752205624.915858:40222:19
Numbas.store[method_name]@https://syd.scorm.canvaslms.com/courses/sconeID/scone_prod.sha256_2a60b51e63de910afc54993a0ec5fe90ad8151200843f8d6aaed4212c71da175/0/scripts.js?build_time=1752205624.915858:41745:48
resume/<@https://syd.scorm.canvaslms.com/courses/sconeID/scone_prod.sha256_2a60b51e63de910afc54993a0ec5fe90ad8151200843f8d6aaed4212c71da175/0/scripts.js?build_time=1752205624.915858:38996:32
on/promise on/promise<@https://syd.scorm.canvaslms.com/courses/sconeID/scone_prod.sha256_2a60b51e63de910afc54993a0ec5fe90ad8151200843f8d6aaed4212c71da175/0/scripts.js?build_time=1752205624.915858:39725:24

[Ben Brawn]

I managed to get the error on chrome too which seemed to give more clues 

Numbas Error: Error loading question 4: Variable x is not defined.

Numbas Error
at new Numbas.Error (https://syd.scorm.canvaslms.com/courses/sconeID/scone_prod.sha256_2a60b51e63de910afc54993a0ec5fe90a…
at c.loadQuestion (https://syd.scorm.canvaslms.com/courses/sconeID/scone_prod.sha256_2a60b51e63de910afc54993a0ec5fe90a…
at Numbas.store. [as loadQuestion] (https://syd.scorm.canvaslms.com/courses/sconeID/scone_prod.sha256_2a60b51e63de910afc54993a0ec5fe90a…
at https://syd.scorm.canvaslms.com/courses/sconeID/scone_prod.sha256_2a60b51e63de910afc54993a0ec5fe90a…
at https://syd.scorm.canvaslms.com/courses/sconeID/scone_prod.sha256_2a60b51e63de910afc54993a0ec5fe90a…
at new Promise ()
at https://syd.scorm.canvaslms.com/courses/sconeID/scone_prod.sha256_2a60b51e63de910afc54993a0ec5fe90a…

[Ben Brawn]

Removing question 4 from a copy of the exam results in the error message indicating question 3 is the issue. 

[Ben Brawn]

ok so obviously question 5 was the actual issue. This question has a bunch of javascript stuff for jsxgraph so that's probably it. We will replicate it using GeoGebra, I guess. I'll leave a copy of the original problem question in case it helps identify an actual numbas issue or in case it's my own script that's an issue and it's an easy fix. https://numbas.mathcentre.ac.uk/question/share/view/fd7b5668-11f4-4692-9235-af9417eefaff 

[Ben Brawn]

After replacing it with ggb and removing all JavaScript functions, we are still having issues with the exam breaking in Canvas in the same way (after closing the exam and resuming it a few times).

[Christian Lawson-Perfect]

The problem is nothing to do with your javascript or with geogebra - there was a bug in the code that serialises variable values. You have a list of LaTeX expressions, defined in the form `latex(safe("..."))`. Only the `latex` wrapper was saved to the suspend data, omitting the `safe` wrapper.

I've fixed that bug, so this error shouldn't come up any more with new attempts.

--
You received this message because you are subscribed to the Google Groups "Numbas Users" group.
To unsubscribe from this group and stop receiving emails from it, send an email to numbas-users...@googlegroups.com.
To view this discussion, visit https://groups.google.com/d/msgid/numbas-users/2e0d14f6-8450-4110-af35-cb806552e479n%40googlegroups.com.