Debugging Elisp

To debug elisp programs, use Edebug.


  1. Instrument the function to debug (i.e. add debugging symbols). Cu C-M-x (prefix + eval-defun).

    Now, any call to the function pauses the interpreter and Edubg at the start of the function.

  2. Call the function.
  3. Pres SPC to step through forms.


  • b Set a breakpoint
  • g Execute until a breakpoint
  • q Exit
  • ? Help

Backtrace Buffer

  • +/- Expand/contract (over multiple lines) the frame at point