stepping after a break

[sshteingold@cctrading.com]

     Bruno posted this:
     
     ;;; 1997-11-03 Mon 09:37:59 EST
     ;;; from Bruno Haible <haible@ma2s2.mathematik.uni-karlsruhe.de>
     #+clisp
     (defun step-on ()
       "Turn on stepping after break."
       (declare (compile))
       (setq sys::*step-level* 0
             sys::*step-quit* most-positive-fixnum
             *evalhook* #'sys::step-hook-fn))
     #+clisp
     (defun step-off ()
       "Turn off stepping. `continue' to proceed."
       (declare (compile))
       (setq sys::*step-quit* 0))
     
     
     I put a break into the code and when I hit it, tried to step. No way:
     
     
     1. Break> (step-on)
     
     #<compiled-closure system::step-hook-fn>
     1. Break> step
     
     step 1 --> step
     Step 1> 
     *** - EVAL: variable step has no value
     2. Break> abort
     1. Break> ?
     
     Help   = this command list
     Abort  = abort to the next recent input loop
     Unwind = abort to the next recent input loop
     Mode-1 = inspect all the stack elements
     Mode-2 = inspect all the frames
     Mode-3 = inspect only lexical frames
     Mode-4 = inspect only EVAL and APPLY frames (default)
     Mode-5 = inspect only APPLY frames
     Where  = inspect this frame
     Up     = go up one frame, inspect it
     Top    = go to top frame, inspect it
     Down   = go down one frame, inspect it
     Bottom = go to bottom (most recent) frame, inspect it
     Backtrace-1 = list all stack elements
     Backtrace-2 = list all frames
     Backtrace-3 = list all lexical frames
     Backtrace-4 = list all EVAL and APPLY frames
     Backtrace-5 = list all APPLY frames
     Backtrace   = list stack in current mode
     Break+ = set breakpoint in EVAL frame
     Break- = disable breakpoint in EVAL frame
     Redo   = re-evaluate form in EVAL frame
     Return = leave EVAL frame, prescribing the return values
     Continue = continue evaluation
     
     1. Break> where
     EVAL frame for form (break)
     1. Break> (step-off)
     
     step 1 --> (step-off)
     Step 1> step
     
     step 1 ==> value: 0
     0
     1. Break> step
     
     *** - EVAL: variable step has no value
     2. Break> 
     1. Break> (step-on)
     
     #<compiled-closure system::step-hook-fn>
     1. Break> (step-on)
     
     step 1 --> (step-on)
     Step 1> step
     
     step 0 ==> value: #<compiled-closure system::step-hook-fn>
     #<compiled-closure system::step-hook-fn>
     1. Break> step
     
     step 1 --> step
     Step 1> step
     
     *** - EVAL: variable step has no value
     2. Break> 
     1. Break>