Re: bug in optional argument processing (?)

On Thursday 23 March 2006 08:33 pm, Ralf Juengling wrote:
> 
> Here is what Lush does:
> 
> ? (defparameter *global-val* 5)
> = *global-val*
> ? (defun f (val &optional (other-val *global-val*))
>      (+ val other-val))
> = f
> ? (f 12)
> 
> *** + : not a real number : *global-val*
> Debug toplevel [y/N] ?n
> ?

That is because the default values of optional arguments are not evaluated.
Workaround

(de f(val &optional other-val)
  (setq other-val (or other-val *global-val*))
  (+ val other-val) )

I simply did not want to introduce another source of dependencies
between the behavior of a function and the dynamical calling context.

- L.


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