Now I'm leaning schemer by looking the book The Seasoned Schemer.
I writed the code by racket, however when I using the try, the schemer didn't have this method or macro. And It reported expand: unbound identifier in module in: try.
The code as the below: (in the page 89)
(define (remove-member-first* a lat)
(try oh (rm a lat oh) lat))
I've search the racket documents, but didn't find smiliar function.
So who does know whether there are kinda function like the 'try'?