[plt-scheme] Names in signatures

Yeah, you just cannot do that. You'd have to write something like this:

(define-signature catenable-list-extensions^
   (append))

(define-signature catenable-list^
   ((open list^)
    (open catenable-list-extensions^)))

etc..

Robby

On Tuesday, June 3, 2003, at 10:30  AM, Jens Axel Søgaard wrote:

>  For list-related administrative tasks:
>  http://list.cs.brown.edu/mailman/listinfo/plt-scheme
>
>
> Is it possible to do something like the following:
>
>  (define-signature list^
>    (empty cons car cdr))
>
>  (define-signature catenable-list^
>    ((open list^)
>     append))
>
>  (define-signature double-ended-list^
>    ((open list^)
>      snoc))
>
>  (define-signature catenable-double-ended-list^
>    ((open double-ended-list)
>     (open catenable-list)))
>
> The last signature is giving me problems. The syntax checker
> says that some names are defined multple times, and that's
> true. But in this case it on purpose.
>
> NB: I am sitting on a computer without Scheme, so the
> above is not syntax-checked.
>
> -- 
> Jens Axel Søgaard
>
>
>