Review of Jose Armando Garcia Sancio's std.log

[James Miller]

On 7 March 2012 16:43, Jonathan M Davis <jmdavisProg at gmx.com> wrote:
> On Tuesday, March 06, 2012 19:27:35 Andrei Alexandrescu wrote:
>> On 3/6/12 7:04 PM, Jonathan M Davis wrote:
>> > On Tuesday, March 06, 2012 18:19:23 Jose Armando Garcia wrote:
>> >> Fatal and Critical are exactly these continence functions... To
>> >> reiterate. fatal will always assert and critical will always throw. It
>> >> is impossible for the user to disable these things.
>> >
>> > No, because they affect the log level. The concept of throwing and the log
>> > level should be _completely_ separate.
>>
>> Why?
>
> Because the level that you log something at and what you want to do in terms
> of exceptions aren't necessarily related at all. It could easily be that you
> want to log something and then do some series of operations before throwing -
> even if the log level is the most severe level, and you intend to throw an
> Error to kill the program. And as others have pointed out, you might want to
> log a series of messages. Having std.log throw on the first one makes it so
> that you can't log any others.
>
>> > std.log shouldn't be declaring _any_
>> > exception types unless they're related to setting up the logging (_none_
>> > which relate to functions which log).
>>
>> Why?
>
> Because as others have asserted, logging should not affect program flow. It's
> printing out messages to a log, which doesn't necessarily have _anything_ to
> do with throwing exceptions. It's merely for providing information about what
> the program is doing. If you have it throwing exceptions - _especially_
> exceptions which are specific to it - you're conflating two separate concepts:
> logging to a log file and having the program report errors. They _can_ be
> related, but they often aren't.
>
> And when you _do_ throw an exception, why on earth would anyone want a
> LoggingException (or whatever std.log would call its exception type)? You want
> an exception which relates to what went wrong, not what threw it. The fact
> that you logged a message before throwing is incidental. Nothing that catches
> the exception is going to care.
>
> - Jonathan M Davis

Surprisingly, I agree with the idea that fatal and critical shouldn't
throw, or at least shouldn't throw by default, maybe a configuration
option would allow for that functionality. Logging probably shouldn't
affect program flow.

Its possible that I may need to log a "critical" error, then do some
graceful shutdown.

In my opinion, critical and error should /not/ throw by default,
however they should be able to get an optional Exception to throw, if
that is appropriate behavior.

--
James Miller