The draft is available here: https://r7rs.org/large/fascicles/proc/

The biggest new feature is the ability to mix definitions and expressions in bodies, such as the body of a lambda. For example, the following is now valid:

(define (map f lst)
  (unless (list? lst)
    (error 'map "not a list" lst))
  (define (map* lst acc)
    (if (null? lst)
        (reverse acc)
        (map* (cdr lst) (cons (f (car lst)) acc))))
  (map* lst '()))

We welcome any and all comments on the draft. Anyone can comment by

• Filing an issue on the R7RS-Large issue tracker,
• Sending mail to the Working Group 2 mailing list,
• Sending mail to the Scheme Reports mailing list )Archives and subscribe), (address)
• Sending mail to the corresponding member Peter McGoron. I will forward your comment to the public issue tracker. Please indicate if you wish to be anonymous.