[armedbear-devel] Performance of ABCL?

[Alessio Stalla]

On Fri, Sep 25, 2009 at 11:47 AM, Žiga Lenarčič <ziga.lenarcic at gmail.com> wrote:
> So the naming of the variables affects the speed? Asterisk around
> names gives faster dynamic variables?

No, using asterisks for global variables only ensures that no local
variable will accidentally become special (and incur in a performance
hit) as the effect of a completely unrelated global variable.

Example:

(defvar x)

(defun f (x) ...) ;x is special
(let ((x ...)) ...) ;x is special

(defvar *x*)

(defun f (x) ...) ;x is lexical
(let ((*x* ...)) ...) ;*x* is special


> Maxima uses too many dynamic variables in general probably - in that
> sense it's a badly written software.

afaik that's because it was originally written in a dynamically scoped Lisp.