(module fs mzscheme
  (provide (all-defined))
  #|"fs.ss -- File utilities, esp for string->symbol conversion and storage"|#
  (define (read-lines f)
    (let readloop ((line (read-line f)) (acc ()))
      (if (eof-object? line)
          (reverse! acc)
          (readloop (read-line f) (cons line acc)))))
  (define (dump fname . data)
    "dump all data to a file"
    (when (file-exists? fname)
        (delete-file fname))
    (call-with-output-file fname
      (lambda (f)
        (for-each (lambda (datum) (write datum f)) data))))
  (define (slurp fname)
    "slurp all data objects from a file, Common Lisp style
Single objects are returned as-is; multiple objects are returned in a list"
    (call-with-input-file fname
      (lambda (f)
        (let ((data ()))
          (do ((datum (read f) (read f))) ;need better iterator here
            ((eof-object? datum) (reverse data))
            (set! data (cons datum data)))
          (if (= 1 (length data))
              (car data)
              (reverse data))))))
  (define (read-file fname)
    "Just like slurp, but only reads one datum. So get it right."
    (call-with-input-file fname
      (lambda (f)
        (read f))))
  (define (process-file inf outf f)
    (call-with-output-file outf
      (lambda (o)
        (call-with-input-file inf
          (lambda (i)
            (write o (f (read i))))))))
  (define (process-file-vars inf outf f)
    (call-with-output-file outf
      (lambda (o)
        (call-with-input-file inf
          (lambda (i)
            (do ((datum (read i) (read i)))
                ((eof-object? datum) (void))
              (write o (f datum))))))))
  (define (process-file-lines inf outf f)
   (call-with-output-file outf
     (lambda (o)
       (call-with-input-file inf
         (lambda (i)
           (do ((line (read-line i) (read-line i)))
               ((eof-object? line) (void))
             (write o (f line))))))))
  )