Ruby Debug (ruby-debug)

Question:
I was wondering if there was a way to instruct the ruby debug
framework to stop/break/freeze on any error so I can investigate the
call stack to diagnose the problem?

Background:
I am using 'ruby-debug' and know that I can insert breakpoints with
the debugger() method call in my code. I have run into errors within
unexpected callbacks and often have no idea why the code traversed
that path. Because I don't understand the code path it's hard to know
where to put the breakpoint to troubleshoot the problem.

- Thanks in advance.

This list is for discussion of Rails internal development, not general
ruby questions.

Having said that, check out the 'cat' (catchpoint) functionality in
ruby-debug...