leverich@randvax.UUCP (Brian Leverich) (11/03/88)
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 -- "Simulate it in ROSS" Brian Leverich | U.S. Snail: 1700 Main St. ARPAnet: leverich@rand-unix | Santa Monica, CA 90406 UUCP/usenet: decvax!randvax!leverich | Ma Bell: (213) 393-0411 X7769