On Thu, Feb 16, 2012 at 7:57 AM, Sönke Ludwig <lud...@informatik.uni-luebeck.de> wrote: > Am 16.02.2012 10:21, schrieb Jonathan M Davis: >> >> On Monday, February 13, 2012 16:50:04 David Nadlinger wrote: >>> >>> Please post all feedback in this thread, and remember: Although >>> comprehensive reviews are obviously appreciated, short comments are very >>> welcome as well! >> >> >> Why does vlog even exist? It's a needless complication IMHO. Let the log >> levels manage what does and doesn't get logged. I see no reason to add the >> concept of verbosity on top of that. It's a needless complication. >> >> Also, _please_ add a debug level. Personally, I'd argue for simply copying >> syslog's levels and matching them, since ideally any logging on Linux >> would be >> going to syslog anyway. But there are good reasons to have messages beyond >> info. I sure wouldn't want _all_ messages which don't indicate a problem >> in >> the app to be marked as info. For instance, what if I want to have info >> displayed in release mode but want greater verbosity in debug mode? I'd >> need >> another log level which isn't there. Using the concept of verbosity to try >> and >> handle this is a needless complication. syslog has >> >> #define LOG_EMERG 0 /* system is unusable */ >> #define LOG_ALERT 1 /* action must be taken immediately */ >> #define LOG_CRIT 2 /* critical conditions */ >> #define LOG_ERR 3 /* error conditions */ >> #define LOG_WARNING 4 /* warning conditions */ >> #define LOG_NOTICE 5 /* normal but significant condition */ >> #define LOG_INFO 6 /* informational */ >> #define LOG_DEBUG 7 /* debug-level messages */ >> >> And I'd like to at least see notice and debug added. >> > > Well in addition to Debug I would also like to see Trace but it's f. ex. > hard for me to tell the difference between Info and Notice and their names > do not imply that certain severity order IMO.
Yes. I would really like to avoid adding more severities because it complicates the decision the developer needs to make when deciding at which log level to log. This reminds of a situation that came up at a previous employer. A bunch of smart people tried to come up with a policy for deciding at which log level to log a particular message. Let just say that the discussion lasted days and no decision was made. I believe that the only reason why this subject even came up at my previous job is because most logging framework provide hard-coded levels that don't have any semantic difference between them. Interesting talk on the subject: http://www.ted.com/talks/barry_schwartz_on_the_paradox_of_choice.html > So I see a point in the > argument that vlog() allows everyone to be happy without endless numbers of > predefined log levels.. however I'm also not quite convinced. > > >> While we're at it, what's the point of dfatal? Why on earth would a >> _fatal_ >> condition not be fatal if it were in release mode if it were fatal in >> debug >> mode? Is it fatal or not? It seems to me like another needless >> complication. >> >> If you're going to have write, then have writef, not format. Then it's >> actually consistent with our normal I/O functions. Also, do writef and >> format >> automatically append a newline? If so, then they should be writeln and >> writefln. >> > > I think the names should be as short as possible for the common 99% case. As > this is not a general purpose stream, I think it is fine to drop the 'ln'. > And the current version that defines info("") as the version that can format > and info.write("") as the plain string version seems to be quite optimal in > this regard. > > In my optinion, more descriptive names would just impair readability here > instead of helping. They will be written endless number of times but do not > influence the program flow and should immediately understandable by anyone > who sees them. But something like log.warn/logf.warn or log.warn/log.warnf > might also work if you really want the consistency... > As of right now (or in the immediate future) we have: info("%s message", Severity.info); info.write(Severity.info, " message); info.writef("%s message", Severity.info); Thanks! -Jose > >> Rich is a horrible name IMHO. It says nothing about what it actually is or >> does. I'm not sure what a good name would be (BoolMessage?, LogResult?), >> but >> Rich by itself is very confusing and utterly uninformative. >> >> And why does Configuration's logger property throw if you set it after a >> logging call has been made. Is it really that inconceivable that someone >> would >> swap out loggers at runtime? Or is the idea that you'd swap out the >> Configuration? >> >> - Jonathan M Davis > >
