Re: General Approach to Troubleshooting Inferior Process

[Pascal J. Bourguignon]

formido <formido@gmail.com> writes:

> So, I installed the elisp packages for inferior ruby and and ruby
> mode. Using the repl in the interpreter works correctly. However,
> sending the ruby process a function definition, or evaluating a region
> if it's a function definition, fails. It errors with, 'cannot make nil
> into string' or some such.


Well you would have to debug emacs lisp code.  Are you ready to do that?
The first step would be to enable the debugger:
M-x set-variable RET debug-on-error RET t RET


But in my experience, when there is this kind of errors on executing
some basic emacs command,  it's because the el package installed
doesn't match the version of emacs used.

Perhaps you have or had a different version of emacs installed in
/usr/local and some .el from /usr/local/share/emacs are used by
/usr/bin/emacs?  


> In general, what sorts of things could I do to troubleshoot this? The
> first thing I thought of was 'well, what's emacs *actually* sending to
> the process?' It uses a function 'process-send-region' which
> apparently takes a starting point and ending point in the target
> buffer. What function can I use to display the text between those two
> points?

(buffer-substring start end) will return a string containing the text
between start and end in the current buffer.


-- 
__Pascal Bourguignon__                     http://www.informatimago.com/

"Debugging?  Klingons do not debug! Our software does not coddle the
weak."