[plt-scheme] The Scheme way of: Using 'global' variables ?

Matthias Felleisen <matthias at ccs.neu.edu> writes:

> use classes instead:
>
> #lang scheme
>
> (define the-function%
>   (class object%
>     (init-field var)
>     (define/public (var++) (set! var (+ var 1)))
>     (define/public (display) (printf "~s\n" var))
>     (super-new)))
>
> (define the-function (new the-function% [var 0]))
> (send the-function display) ;; => 0
> (send the-function var++)
> (send the-function display) ;; => 11
>
>
> It really scales.

But the class methods can only be defined statically inside
the class (or its parents), right?  How does that scale more
than a traditional dispatch handler?

-- 
Alex