Remove allowing string argument in (read)

[jcubic]

This will be real braking change, but the code doesn't work correctly anyway:

(let ((x "1 2 3"))
  (write (read x))
  (newline)
  (write (read x))
  (newline))
;; ==> 1
;; ==> 1

You will still be able to use lips.parse, to get the same behavior:

(let ((x "1 2 3"))
  (write (. (lips.parse x) 0))
  (newline)
  (write (. (lips.parse x) 0))
  (newline))

With this the read can be patched to get the old behavior:

(define read (let ((read read))
               (lambda (arg)
                 (if (string? arg)
                     (. (lips.parse arg) 0)
                     (read arg)))))

[jcubic]

with idiomatic Scheme you can use string ports from SRFI-6.

(let* ((str "(1 2 3)")
       (port (open-input-string str)))
   (with-input-from-port port read))
;; ==> (1 2 3)

(define read (let ((read read))
               (lambda (arg)
                 (if (string? arg)
                     (let* ((port (open-input-string arg)))
                        (with-input-from-port port read))
                     (read arg)))))

[lassik]

Traditional:

(read-from-string "1 2 3") ; => 1

(with-input-from-string "1 2 3" read) ; => 1

(with-input-from-string "1 2 3" read-all) ; => (1 2 3)

I recommend adding with-input-from-string and read-all. They are generally useful. Gambit has both.

[jcubic]

Thanks, for the tip.

[jcubic]

It seems that with-input-from-string is even in WikiBook about Scheme. BTW: it's worth linking to this book from the website.

[lassik]

Also in Common Lisp.

I'll add a link to the wikibook, thanks!