Re: Working with constansts

[Nikolaj Schumacher <me@nschum.de>]

Richard Riley <rileyrgdev@googlemail.com> wrote:

>> Because this would incur overhead on every assignment, as it would have 
>> to check whether the variable being assigned was declared as a constant.  
>> Since this is so rarely the case, this overhead could be seen as mostly 
>> wasted and unnecessary.
>
> I don't know enough about Lisp than I can only assume that in this case
> it can not be detected at compile time IF you compile to byte/p code.

"Thanks" to dynamic scoping it cannot be caught at compile time.

(defconst xxx nil)

(defun change-xxx ()
  (setx xxx t)) ;; const or variable?

(let ((xxx nil))
  (change-xxx))


regards,
Nikolaj Schumacher