[plt-scheme] define-syntax help

I agree that it is less than clear, but I think that what is trying to be done
is to have the hash table populated at syntax time.

To do this, the defines
should be changed to define-for-syntax, and

#`(hash-table-put! *field-hash* (make-key 'mod 'sym) val))))

should become something like

(begin
  (hash-table-put! *field-hash* (make-key 'mod 'sym) val)
  #'(whatever you want at run time))

Read section 12.3.3 of the language manual, and things should be clearer,
at least you can ask a question that is likely to be answered.



On 3/22/07, Noel Welsh <noelwelsh at yahoo.com> wrote:
> Perhaps I'm missing something.  Why not make these functions?
>
> N.
>
>
>
> ----- Original Message ----
> From: "support at taxupdate.com" <support at taxupdate.com>
>
> Given the following:
>
> ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
> (define *field-hash* (make-hash-table))
> (define (make-key mod sym)
>   (string->symbol (format "~a.~a" mod sym)))
> (define-syntax (register stx)
>  (syntax-case stx ()
>   ((_ sym val mod)
>    #`(hash-table-put! *field-hash* (make-key 'mod 'sym) val))))
>
> (reqister you "joe" main)
> (register you "sue" aux)
> ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
>
> ...
>
>
>
>
>
>
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