std.experimental.logger formal review round 3

[Martin Nowak via Digitalmars-d]

On 10/27/2014 09:08 AM, Robert burner Schadek wrote:
>
> And again I'm saying fixing the LogLevel at CT is not good enough. And
> the other part of the solution uses class just like std.logger.

Right, a CT LogLevel only works for certain use-cases and I never 
claimed that it works for everything (that's why there is the 
loggerObject adapter). This not an argument to go solely with classes 
though. And you loose an important optimization by not making use of CT 
LogLevels.
Introducing the concepts and providing the loggerObject adapter (structs 
to interface) is a very flexible solution that proved itself very 
successful for ranges.

> And the hierarchy you're building is also at CT, which is just not gone
> work, if you don't have ultimate control of all sources.

What's the problem here, a counterexample would be helpful.

Logger logger;
if (config.alsoLogToFile)
     logger = loggerObject(multiLogger(SysLogger(), FileLogger()));
else
     logger = loggerObject(SysLogger());