디버그

(declaim (optimize (debug 3) (speed 0) (safety 3)))

(declare (ignore arg))

Ref

• https://malisper.me/category/debugging-common-lisp/
• Debugging Lisp: fix and resume a program from any point in the stack - how Common Lisp stands out.
• https://cl-community-spec.github.io/pages/invoke_002ddebugger.html