On Fri, Nov 30, 2012 at 8:29 AM, Jean-Michel HUFFLEN
<[email protected]>wrote:

>     Hello,
>
>     I went up with reading the formal definitions of R7RS.
>
> - p. 72, the definition of the auxiliary macro "guard-aux"; the 5th
> clause reads:
>
> ((guard-aux reraise (test)) test)
>
>     It seems to me that the correct expansion should be:
>
> ((guard-aux reraise (test)) (or test reraise))
>
> - p. 70, "define-values"; the 1st clause
>
> ((define-values () expr) ...)
>
> seems to me to be useless, "define-values" cannot be used with an
> empty list of variables, and no recursive call yields this situation;
>
> - p. 71, "make-parameter": your definition accepts any positive number
> of arguments with :
>
> (define (make-parameter init . o) ...)
>
> Why not using "case-lambda", for "make-parameter" as well as its
> result?


Because this is actually longer than the cond version.

-- 
Alex


> That is,
>
> (define make-parameter
>    (let ((make-parameter-aux
>           (lambda (init converter)
>             (let ((value (converter init)))
>               (case-lambda
>                (() value)
>                ((control) (if (eq? control <param-convert>)
>                               converter
>                               (error "bad parameter syntax")))
>                ((control value-0) (if (eq? control <param-set!>)
>                                       (set! value value-0)
>                                       (error "bad parameter syntax"))))))))
>      (case-lambda
>       ((init) (make-parameter-aux init values))
>       ((init converter) (make-parameter-aux init converter)))))
>
>     Cheers,
>
> J.-M.
>
>
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