s c h e m a t i c s : c o o k b o o k

(require (lib "string.ss" "srfi" "13"))
(define (reindent s num-spaces)
  (let ((lmargin (make-string num-spaces #\space))
        (newline (make-string 1 #\newline)))
    (string-join (map (lambda (a-line) 
                        (string-append lmargin (string-trim a-line))) 
                      (string-tokenize s)) 
                 newline)))

> (display (reindent "one\ntwo\nthree" 3))
   one
   two
   three
> (display (reindent "one\n     two\n  three" 3))
   one
   two
   three