I'm trying to debug Lisp code in the Logon system. I know how to use the debugging-by-printing method, but it would be more effective to step through the code line by line. I'm trying to figure out how to do this.<div>
<div><div><br></div><div>I know next to nothing bout Lisp and am stumped as to what to type at the REPL prompt. I've done a lot of Googling for references about Lisp debugging, but there doesn't appear to be a canonical source or a standard way that debugging works.<div>
<br></div><div>I know no one has the time to teach me Lisp, but if someone could respond with a link to a webpage with good info or some hints on what to type next it would help me a lot. Here is what I've done so far.</div>
<div><ol><li>Start the logon system inside of emacs.</li><li>Added a (break) command to the top of the lisp function I want to step through.</li><li>Called (load ...) on the source file into which I inserted the break.</li>
<li>Run the function.</li></ol><div>I am dropped into a debugger prompt.</div><div><br></div></div></div></div></div><blockquote class="webkit-indent-blockquote" style="margin: 0 0 0 40px; border: none; padding: 0px;">Break: call to the `break' function.<br>
<br>Restart actions (select using :continue):<br> 0: return from break.<br> 1: Return to Top Level (an "abort" restart).<br> 2: Abort entirely from this (lisp) process.<br>[1c] TSNLP(12): help<br>Error: Attempt to take the value of the unbound variable `HELP'.<br>
[condition type: UNBOUND-VARIABLE]<br></blockquote><div><div><div><div><div><br></div><div>Now I'm stumped as to what to type next. I can do :bt to get a stack.</div><div><br></div></div></div></div></div><blockquote class="webkit-indent-blockquote" style="margin: 0 0 0 40px; border: none; padding: 0px;">
1c] TSNLP(5): :bt<br>Evaluation stack:<br><br>SUMMARIZE-FOLDS <-<br> EVAL <- TPL:TOP-LEVEL-READ-EVAL-PRINT-LOOP <- TPL:START-INTERACTIVE-TOP-LEVEL<br><br><br>(to see any ghost frames, the disassembler must be loaded)<br>
</blockquote><div><div><div><div><div><div><br></div><div>But my attempts to run other commands (including getting a help menu for this prompt) have failed. You'd think it would be easy to Google-up instructions on what to do at this point, but I haven't found a definitive source. Can someone tell me how to:</div>
<div><ol><li>Do basic command line actions from this prompt: backtrace, list source, step, next, set breakpoints, and evaluate variables.</li><li>Select the numbered options that show up in this menu.</li></ol></div></div>
<div>A pointer to a good Lisp debugging page would probably do the trick for me.</div><div><br></div><div>Thanks.</div>-- <br>W.P. McNeill<br><a href="http://staff.washington.edu/billmcn/index.shtml">http://staff.washington.edu/billmcn/index.shtml</a><br>
Sent from Seattle, WA, United States
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