Stackless exception (RUnit?)

I find that often I want to raise an exception, with an error message
that tells the Programmer what he’s done wrong. However, I don’t want a
long stack trace when this happens. What I’ve been writing is:

raise “Foo not support here”

And, I definately get a big stack trace when I run my unit-tests, but
also when used in an application… I’d like to see something that told
me the error message, and what line it happened at, but no much more.
(Much like I remember Perl’s “die”).

What’s the best way to do this in Ruby?

David Corbin