On Jul 8, 2012, at 7:25 AM, Daniel King wrote: > (define (stream-map f s) > (unless (procedure? f) (raise-argument-error 'stream-map "procedure?" f)) > (unless (stream? s) (raise-argument-error 'stream-map "stream?" s))
On a related note, the above kind of checks should really become real contracts. -- Matthias > (let loop ([s s]) > (cond > [(stream-empty? s) empty-stream] > [else (stream-cons (call-with-values (lambda () (stream-first s)) f) > (loop (stream-rest s)))]))) _________________________ Racket Developers list: http://lists.racket-lang.org/dev
