( with-exception-handler [ procedure? handler ] [ procedure? thunk ] ) *
handler ( λ obj ) *
thunk ( λ ) *
It is an error if handler does not accept one argument. It is also an error if thunk does not accept zero arguments. The with-exception-handler procedure returns the results of invoking thunk. Handler is installed as the current exception handler in the dynamic environment used for the invocation of thunk.
( xcons d a ) pair?
(lambda (d a) (cons a d)) Of utility only as a value to be conveniently passed to higher-order procedures.
( zip [ list? clist1 ] [ list? clist2 ] ... ) list?
(lambda lists (apply map list lists)). If zip is passed n lists, it returns a list as long as the shortest of these lists, each element of which is an n-element list comprised of the corresponding elements from the parameter lists. At least one of the argument lists must be finite.