[plt-scheme] Linking Scheme- and C-variables

[snip]
>   (module hooked-vars mzscheme
>     (provide def-hooked-var)
>     (define-syntax (def-hooked-var stx)
>       (syntax-case stx ()
>         ((_ var val hook) (identifier? #'var)
>          (with-syntax ((hidden-var
>                         (datum->syntax-object
>                          #'var
>                          (string->symbol
>                           (string-append
> (symbol->string (syntax-e #'var))
>                                         
> "-hidden-value"))
>                          #'var)))
>            #'(begin (define hidden-var val)
>                     (define-syntax var
>                       (make-set!-transformer
>                        (lambda (stx)
>                          (syntax-case stx (set!)
>                            ((set! var new-val)
>                             #'(set! hidden-var (hook
> new-val)))
>                            ((var . xs) #'(hidden-var
> . xs))
>                            (var       
> #'hidden-var)))))))))))
> 
> For example:
> 
>   > (require hooked-vars)
>   > (define a 1)
>   > (def-hooked-var b 1 (lambda (new) (set! a new)
> new))
>   > (set! b 3)
>   > b
>   3
>   > a
>   3

That will link them in MzScheme, but from C's point of
view, b would still only be accessable as a
Scheme_Object*, right?


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