[armedbear-devel] How to use ABCL's debugger

[Erik Huelsmann]

Hi David,

On Mon, May 16, 2011 at 8:35 PM, David C Wang <davidcw at mit.edu> wrote:
> I recently started using ABCL, and until now I've been able to use it
> fine through the Emacs/Slime interface.
>
> I'm now trying to use ABCL directly from the command line, but I have
> no idea what the debugger commands are.
> Once a runtime error occurs and I am offered the list of possible
> restarts, how do I check the current frame and step through the
> backtrace?

:bt <num> lists the last <num> frames in the stack. These additional
commands are available:

D:\abcl\abcl-j>abcl
Armed Bear Common Lisp 0.26.0-dev-svn-13273:13274M
Java 1.6.0_20 Sun Microsystems Inc.
Java HotSpot(TM) Client VM
Low-level initialization completed in 1.434 seconds.
Startup completed in 5.417 seconds.
Type ":help" for a list of available commands.
CL-USER(1): :help

  COMMAND     ABBR DESCRIPTION
  apropos     ap   apropos
  bt               backtrace n stack frames (default 8)
  cd               change default directory
  cf               compile file(s)
  cload       cl   compile and load file(s)
  continue    cont invoke restart n
  describe    de   describe an object
  error       err  print the current error message
  exit        ex   exit lisp
  frame       fr   set the value of cl:* to be frame n (default 0)
  help        he   print this help
  inspect     in   inspect an object
  istep       i    navigate within inspection of an object
  ld               load a file
  ls               list directory
  macroexpand ma   macroexpand an expression
  package     pa   change *PACKAGE*
  pwd         pw   print current directory
  reset       res  return to top level
  rq               require a module
  trace       tr   trace function(s)
  untrace     untr untrace function(s)

Commands must be prefixed by the command character, which is ':' by default.

> Is there documentation on this somewhere? Or, can someone tell me what
> some of the basic commands are?

The documentation (as terse as it is) is under :help :-)

The way to select a specific restart is by entering its number.

> I'm running the latest ABCL on Fedora 14 x64.

I hope you like it. If you don't mind me asking: what are you
(planning to) using ABCL for? Scripting language? Main language? Which
area of application? I'm always interested to hear people's stories
about their ABCL experience.


Bye,

Erik.