[racket] possibility of defining recontract-all-from-out

Yes, this is very helpful. Thank you.

-Jon


On Fri, Sep 12, 2014 at 10:47 AM, Matthias Felleisen
<matthias at ccs.neu.edu> wrote:
>
> Does this sketch help:
>
> #lang racket
>
> ;; define a header file language
> (module L racket
>   ;; specification
>   (provide export)
>   ;; ----------------------------------------------
>   ;; implementation
>   (define-syntax (export stx)
>     (syntax-case stx ()
>       [(_ file name ctc)
>        #'(define-syntax (file stx)
>            (syntax-case stx ()
>              [(_)
>               ;; let's break hygiene here:
>               (let* ([x '(provide (contract-out (name ctc)))]
>                      [y (datum->syntax stx x)])
>                 y)]))])))
>
> ;; -------------------------------------------------------
> (module header-file racket
>   (require (submod ".." L))
>   (provide provide-stack)
>   ;; -----------------------------------------------------
>   (export provide-stack make (-> empty?)))
>
> (module good-server racket
>   (require (submod ".." header-file))
>   (provide-stack)
>   ;; -----------------------------------------------------
>   (define (make)
>     '()))
>
> (module bad-server racket
>   (require (submod ".." header-file))
>   (provide-stack)
>   ;; -----------------------------------------------------
>   (define (make)
>     "the empty stack"))
>
> (module client racket
>   (provide
>    (contract-out
>     (test (-> (values string? string?)))))
>   ;; -----------------------------------------------------
>   (require (prefix-in good: (submod ".." good-server))
>            (prefix-in bad: (submod ".." bad-server)))
>
>   (define (test)
>     (values
>      (with-handlers ((exn:fail:contract? (lambda (_) "passed")))
>        (bad:make)
>        "failed")
>      (begin (good:make) "passed"))))
>
> ;; RUN BABY RUN
> (require 'client)
> (test)
>
>
>
>