Re: One more item to the collection of Lua hate-speech

[Joshua Jensen <jjensen@...>]

 ----- Original Message -----
From: HyperHacker
Date: 7/5/2010 7:51 AM
> On Mon, Jul 5, 2010 at 06:41, Brian Weed<brianw@imaginengine.com>  wrote:
> > > > Lua is probably quite fast already even if you only use global
> > variables, ie, don't bother with locals.
> >
> > That's been our experience.
> >
> > We use Lua to script almost all of our games, and we've never once
> > localized a global (for performance, or any other reason), because it's
> > not a bottleneck, and we don't waste time "optimizing" stuff that's not
> > a bottleneck.
> Premature optimization is the root of all evil, after all.
I shouldn't answer this, but I will anyway.

It is not always possible to optimize at the end of a project when 
bottlenecks are staring you in the face.  Projects have deadlines and 
need to ship.  Making sweeping changes to optimize areas invalidates all 
the QA work done to date.  Many optimizations are also incredibly 
dangerous to make and could easily introduce new problems.

That said, a more appropriate approach would be to ask yourself up front 
if any of the subsystems could become a bottleneck and make the 
necessary changes early.

In my case, if I know that local variables are MUCH faster than using 
globals (and they are), I'll use local variables as a "premature 
optimization".  I wrote it right (for performance) the first time, and 
that means I don't have to revisit that area later.

IMHO.

Josh