Re: Logging in Guile

[Zelphir Kaltstahl]

Hi Roel,

A simple short code is always tempting, thanks. I will check it out!

Regards,
Zelphir

On 1/13/20 10:42 PM, Roel Janssen wrote:
> On Mon, 2020-01-13 at 19:06 +0100, Zelphir Kaltstahl wrote:
>> Hi Guile Users!
>>
>> Is there any library for logging in Guile?
>>
>> What I imagine is something, where I can log messages of various levels,
>> like debug, info, error and such. Currently I am using display and
>> simple-format for all the things, but it would be nice to be able to run
>> a program and give it some log level, so that only the log messages of
>> that level or above in importance are shown. Then I could leave all my
>> logging in my code and set it to debug level or, if intended to be seen
>> for the user, set it to info level, or if there really is an error, I
>> could set it to error level.
>>
>> On a quick search I could not find anything.
>>
>> Regards,
>> Zelphir
> I'm using a rather simple module that distinguishes errors from warnings and
> debug:
> https://github.com/UMCUGenetics/sparqling-genomics/blob/master/web/logger.scm
>
> You could implement your own log levels easily..
>
> So you can use it like this:
> (log-error "the-calling-function" "A ~a ~a ~a" "format" "like" "format")
> (log-debug "the-calling-function" "Similar to ~a" 'log-error)
> (log-warning "the-calling-function" "Similar to ~a" 'log-debug)
>
> Then there are three functions that return a port to write to:
> (default-error-port) (default-warning-port) (default-debug-port)
>
> When (null? port) => #t, no message is written.
>
> See:
> https://github.com/UMCUGenetics/sparqling-genomics/blob/dc5fea515c30aa26ff60b77911438689473d125b/web/ldap/authenticate.scm.in#L148
>
> Kind regards,
> Roel Janssen
>
>