Re: [boost] Re: logging lib, v1.3

From: Caleb Epstein (caleb.epstein_at_[hidden])
Date: 2004-10-29 23:09:26

On Fri, 29 Oct 2004 13:26:34 +0400, Maxim Yegorushkin <e-maxim_at_[hidden]> wrote:
> Daniel Frey <daniel.frey_at_[hidden]> wrote:
> 
> >>     logger("app.gui") << "something GUIsh";
> >>  Though I am not sure, if a compiler will be able to optimize checks
> >> for every operator<<() to a single check for the entire output
> >> expression.
> >
> > Now replace "something GUIsh" with anExpensiveFunction(). John's code
> > will not evaluate it when the logger is disabled. OTOH your code will
> > always evaluate it, which is IMHO not acceptable for a logging library.
> 
> Well, that is true, though my logging needs has never required calling any
> expensive functions.

All of the iostreams functions add up fast.  Its a huge win to not
have to evaluate them if you're not going to log the message.  Its a
must-have feature.

-- 
Caleb Epstein
caleb.epstein_at_[hidden]