Re: New (only?) extensible logging package for Emacs

[Eli Zaretskii]

> From: Matúš Goljer <matus.goljer@gmail.com>
> Cc: yantar92@posteo.net, emacs-devel@gnu.org
> Date: Mon, 13 Mar 2023 16:59:49 +0100
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> > I hope the log will end up in Emacs buffers, or at least that there
> > will be an option to do so.  While other logging frameworks are
> > designed to work with programs that leave log files, in Emacs it is
> > customary to have the log in a buffer (and then the user can save that
> > buffer if needed).
> 
> If you mean the "info" level logs I said we can log with message (the
> function), they would end up in *Messages* but of course can go to some
> other separate buffer.

*Messages* is not the best idea: in any long-running session, it is
full of uninteresting messages, and also wraps around after
message-log-max messages (and the default value of message-log-max is
quite low for serious logging).

So yes, I think these logs should go to a separate buffer.

> My most immediate use-case for this package is the development of Elsa,
> where I also develop a Language Server for LSP and use emacs-async with
> async workers.  Having flexible appending logic in these subprocesses
> allows me to use the single interface (say lgr-info) to dispatch
> messages to:
> 
> - client via LSP notifications
> - parent process via async-send
> - CLI when running elsa from terminal
> 
> All just by configuring the loggers at the start of each process.
> 
> For use inside Emacs session for debugging etc, a buffer seems like an
> obvious log destination.

Yes.  Moreover, saving a buffer to a file, either from time to time or
based on some other trigger, is trivial.