link="#009900" vlink="#007700" alink="#cc0000"> Teachpacks for How to Design Programs

Directories

dir.ss

The teachpack dir.ss provides two-structures and one operation:

(define-struct dir (names dirs files))

(define-struct file (name size content))

 create-dir which consumes a directory path (a string) 
       and produces a directory.



The teachpack relies on two data definitions: 
 
 
   A directory is 
    (make-dir string[path] (listof directory) (listof file)) 

   A file is  (make-file string[file name]) 


Sample: Set teachpack to dir.ss and execute. Then evaluate 
> (create-dir ".")
(make-dir
  '|.|
  empty
  (cons (make-fil 'ball1.gif 1289 empty)
        (cons (make-fil 'blueball.gif 205 empty)
              (cons (make-fil 'greenbal.gif 204 empty)
                    (cons (make-fil 'redball.gif 203 empty)
                          (cons (make-fil 'ufo.gif 1044 empty)
                                (cons (make-fil 'gif-test.ss 5811 empty)
                                      empty)))))))


Note: Softlinks are always treated as if they were empty files.