Re: [boost] Re: recommend logging library?

From: Darren Cook (darren_at_[hidden])
Date: 2004-03-19 20:11:15

Thanks for the reply. I think your solution solves different problems 
(conditional inclusion; not including streamed data as macro parameter).

Having read other messages in this thread I think I should pass a 2nd param 
to the LOG macro: an identifier that returns the ostream to use. But next 
time I need logging I'll probably try one of the log4J projects mentioned.

Darren

>> The problem comes when I have a function that takes an ostream; then I 
>> have to expose the internals:
>>
>>     LOG("Here is data:");LOG(obj->debug_info(*logfile,true,false));
>>
>> Is there a better way?
>>
> Yes,
> #define SOME_LOG_MACRO( MiscParams) \
>        if ( ! ShouldLog( MiscParams) )  \
>        { /* Don't execute, or log anything */ \
>        } \
>        else /* create something that returns an ostream& derived 
> instance */ (MiscParams).GetStream ()
> 
> You can then use:
> SOME_LOG_MACRO( xxx)  << "foo:" << foo << " bar:" << bar;
> and it will only execute the << methods if logging is enabled, or if 
> it's necessary based on whatever you define.  Plus, the streamed data 
> doesn't have to be included in the macro as a parameter.
> 
> Cheers...
> 
> _______________________________________________
> Unsubscribe & other changes: 
> http://lists.boost.org/mailman/listinfo.cgi/boost
> 
> 
>