Re: [boost] [log] Boost.Log formal review

Subject: Re: [boost] [log] Boost.Log formal review
From: Thomas Klimpel (Thomas.Klimpel_at_[hidden])
Date: 2010-03-12 06:04:24

Roland Bock wrote:
> Barend Gehrels wrote:
> [snip]
> > However, what might happen is that if there is an attractive logging
> > library, Boost library writers start to use it, of course. All
> libraries
> 
> Why would they? I'd say logging is done by an application, not by
> generic libraries.

This is an excellent point.

As a remark a bit offtopic for the review of a logging library, I think the following can be said about libraries:
Libraries have to communicate "errors", "warnings" and "informations" back to their "client":

* The communication of "errors" is easy, just throw an exception.

* The communication of "warnings" is more challenging, since the library has to continue its work. So "warnings" must be "aggregated" as they arise and reported back when the library has finished its work. The "aggregation" means among others, that certain "warnings" are only reported and stored once (take "somebody included a deprecated header" warning of gcc as an example).

* The communication of "information" is not necessarily challenging, but leads to the question which "information" is really interesting and should be reported. This is most closely related to the task of a logging library. This is also a broad domain, as there is such diverse "information" as "progress report", "work summary" and "???". What this information has in common is that it is not really important for the program logic, so it can be switched on and off via some sort of "verbose" flag.

Regards,
Thomas