TRAPPING ERRORS IN TI'S PC-SCHEME

[leverich@rand-unix.arpa (Brian Leverich)]

Deep in the bowels of a hunk of TI's PC-Scheme code, I'm running what
amounts to a read-eval-print loop of my own (where the user is using
the ROSS simulation language defined in Scheme, rather than Scheme itself).

What I'd like to do is trap all errors, _including errors that would
normally be trapped by Scheme_, and handle them in my own way.  Problem
is that any time Scheme sees a glitch it dumps the user into the Scheme
break package, and the user has to manually extricate himself/herself.

In LISP implementations of ROSS we've done some magic with catches and
throws to shelter the user from the tender mercies of the break package.
Is there some TI PC-Scheme magic, using continuations or whatever, that
would allow ROSS to evaluate a user-input expression, return the value of
the expression if it evaluated successfully, or return a flag _without
invoking the break package_ if the expression causes a Scheme error?

Tnx for advice...  -B
-- 
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  Brian Leverich                       | U.S. Snail: 1700 Main St.
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