;;;; string-utils.scm  -*- Scheme -*-
;;;; Kon Lovett, Jul '18
;;;; Kon Lovett, Aug '10

(module string-utils

(;export
  string-fixed-length)

(import scheme
  (chicken fixnum)
  (chicken type)
  (only memoized-string make-string+)
  (only type-checks check-char check-string check-fixnum ))

(: string-fixed-length (string fixnum #!rest --> string))
;
(define (string-fixed-length s n #!key (pad-char #\space) (trailing "..."))
  (let (
    (rem
      (fx-
        (check-fixnum 'string-fixed-length n)
        (string-length (check-string 'string-fixed-length s)))) )
    (if (positive? rem)
      (string-append s (make-string+ rem (check-char 'string-fixed-length pad-char)))
      (let (
        (lim (fx- n (string-length (check-string 'string-fixed-length trailing)))) )
        (if (positive? lim)
          (string-append (substring s 0 lim) trailing)
          trailing ) ) ) ) )

) ;module string-utils