> The solution that springs to mind is to choose which class to instantiate
> with (if (list? param-a) ,,,) but then I'd have to state the parameter lists
> twice.
Hi Kieron,
Can you choose the class using an if or cond?
For example:
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
(define (try-it x)
(define the-class%
(if (list? x) multi-item-representer% item-representer%))
(define r (new the-class% [param-a x] [param-b 50] [param-c "yellow"]))
(send r print))
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
This bit of code binds the-class% at runtime to one of those classes,
depending on x.
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