Re: [boost] New Logging Library

From: Darren Cook (darren_at_[hidden])
Date: 2005-02-15 20:30:35

>> Hhmm, no, I've lost the ability to write:
>>   LOG("a="<<a<<",b="<<b);
> 
> ...  The reason is that the basic_entry requires the creation 
> and usage of an ostringstream which is a fairly heavyweight object.  It 
> all depends really on what you want x to be.  If x were always going to 
> be a string literal for example, you could have instead:

x is hardly ever a string literal, so I can accept the ostringstream overhead.

Taking a step back, many of my log lines are exactly like the above example, 
so a very useful macro would work like John Torjo's smart assert and I could 
write:
    LOGVARS(a)(b);

As my macro will insert file/line/function name I generally don't need to 
write anything else.

> (unless of course you have a global log called alm, as it seems you would
> need to have by your macro, in which case you could omit the first
 > parameter).

This is how I currently do it: global logs with different macros to write to 
each. But my current logging is too inflexible, so, yes, I should switch to 
a single macro with logname as the first parameter.

Darren

P.S. Even better would be able to write LOGVARS(*) and have it log all 
function parameters and local vars that are currently in scope. Is this 
something that the Wave library could do, or does it require a full C++ parser?