Re: [Scheme-reports] Formal definitions [con'd]

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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