I don’t see anything wrong with your script, except that you lose the selection if something is already selected (but this can be fixed by unselecting first with (send ted set-position current current))

HahaHaHa… I had merely written an infinite loop, what a nθθb…

https://racket.slack.com/archives/C8FS3SS22/p1588599284104900 — I’ve gotten this 3 more times today. No rhyme/reason that I can see. Just click “run” (on a simple GUI program), close the resulting window and the error pops up. Click “run” again, doesn’t happen. Doesn’t happen again for 30 minutes then it happens again.

If anyone here has something they’d like me to inject somewhere to try and zero in on this, I’m happy to.

You asked about byte vs utf–8 positions recently, so I was wondering if the current problem involves characters where those would differ. The posted script is very simple, yet (sometimes) permanently messed up indentation, or tokenization, or something like that (again, unfortunately I don’t recall precisely which/how). I may even have tried a version that inserted ascii characters and the problem went away, but don’t have a record/memory of that debugging — it was a one-off to convert a few files so it was soon quicker to just do it manually. In short, I’m suggesting that if you’re trying to narrow down the problem, and there are non-ascii characters involved, try separating out that aspect.

Thanks for the idea, I’m keep our in mind!

@massung This is odd. I’ve been doing simple gui stuff all afternoon (frame%, canvas% , timer%) Can you log this as an issue against DrRacket on github? https://github.com/racket/drracket/issues/new Please @ mention me @spdegabrielle in the issue

Done.