[slime-devel] hacking system internals from Slime

[Helmut Eller]

* Nikodemus Siivola [2008-12-01 09:50+0100] writes:

> Here's a workflow issue that I run into periodically:
>
> 1. While working on SBCL I instrument some internal operation to see
> what is going on -- let's say with BREAK.
>
> 2. Before I can run my test-case I need to page my way thru a number
> of debugger entries (sometimes a HUGE number) due to eg. cursor
> movement in a Lisp buffer causing the instrumented operation to be
> used.
>
> I'm not looking for a 100% solution, because I doubt anything like
> that exists. Hacking a live system is always tricky that way...
>
> An 80% solution might be being able to tell Slime to stop talking to
> the lisp, except for communications triggered by explicit REPL
> evaluations. Does this sound like a feasible idea? Any other
> suggestions?

I'm not sure that I understand your problem.  One problem that I
encountered is that calling BREAK inside the compiler isn't very
feasible because SLIME calls the compiler for other reasons too.

For this situation I use this special break function:

  (defvar *break-in-compiler* nil)

  (defun compiler-break (&rest args)
    (when *break-in-compiler*
      (apply #'break (or args (list "compiler-break")))))

  (compile 'compiler-break)

  (defun debug-compile-defun (s)
    (let ((*break-in-compiler* t)
          (c::*check-consistency* t))
      (with-input-from-string (in s)
        (ext:compile-from-stream in 
                                 :trace-stream *standard-output*
                                 :verbose t
                                 :print t
                                 :progress t
                                 :byte-compile nil))))

COMPILER-BREAK invokes BREAK only if *BREAK-IN-COMPILER* is true.
To actually invoke the breakpoint I invoke the compiler via 
DEBUG-COMPILE-DEFUN. Usually with this Emacs side command:

(defun slime-debug-compile-defun ()
  (interactive)
  (let ((s (apply #'buffer-substring-no-properties
                  (slime-region-for-defun-at-point))))
    (slime-eval-async `(cl-user::debug-compile-defun ,s)
                      (lambda (x) (message "debug-compile finished")))))


Are you are searching this kind of thing?

Helmut.