Common Lisp Debugging: Essential Tips and Techniques

You are in front of some software written in Common Lisp that doesn't behave as expected... How can you understand what is wrong?

[@FlickeringBytes]

Excellent, thanks for a short and effective presentation 😊

[@vindarel]

Cool! To compile the function with max debug settings, there is also a handy Slime shortcut: C-u C-c C-c.

[@the-lisper]

Thanks for sharing!

[@hem1t0x01]

And what is that command? how do I enable that in sly?

[@vindarel]

@@hem1t0x01 It's "M-x slime-compile-defun" with a prefix argument, and I bet it's the same shortcut in Sly.

[@kensan73]

Wow I needed this 10+ years ago when I was taking a common lisp class. (I don't know how I got any of the programs working with just printing!)

[@the-lisper]

I had been using print for a long time, and it works. But yes, the right setup really shows you what lisp can offer! Maybe, nowadays, it is easier, there are more tutorial/books and pre-configured environments (like portacle).

[@jacekjacenty]

Thank you for the nice explanation.

[@the-lisper]

You're welcome! 😊

[@freddief939]

Looks like Slime doesn't work with Emacs 29 without manually adding some legacy functions to your init.el

[@the-lisper]

I am still on Emacs 28, so I haven't dealt with it. If it doesn't get fixed, I may do a video about it in the future, like a fresh install using a VM!

[@freddief939]

@@the-lisper sly is also available. :)

[@the-lisper]

Yes, it has become my go to choice (as you can see in more recent videos)! :^)
The idea of the first videos was to show the usage of portacle!

[@SynchronizedRandomness]

Sly worked out of the box for me, and had the same features.

[@raba2d723]

awesome, can this be used with elisp?

[@the-lisper]

No, you cannot directly, those features are quite specific to common lisp.

[@raba2d723]

great thanks!