Matthias, Thank you, that's really helpful, both for letting me know I'm not being an idiot (always welcome!) and for the example code, which makes me realise I should learn about exceptions next.
Many thanks again, James ------------------------------- James Geddes -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
