Re: Error handling

[Philip Van Hoof <spam pvanhoof be>]

On Tue, 2006-11-21 at 16:23 +0100, Sergio Villar Senin wrote:
> Philip Van Hoof wrote:
> > We have to do something about them .. errors.
> 
> Sure.
> 
> > I mostly simply ignore them (because my opinion is that too many people
> > develop with ONLY errors in mind, whereas errors should be handled in
> > the highest possible layer -- by displaying an error message -- in case
> > the code can't recover from an error by doing what is expected).
> > 
> > For making it more simple for myself (prioritising things) I simply
> > printed some warnings whenever an error happens.
> > 
> > I know right error handling requires adding a GError** parameter to
> > quite a lot methods. I'm not afraid if such an API change at this
> > moment.
> 
> I agree with that, I don't think tinymail needs a more complicated error
> scheme. I can help with this (not a lot because I'm working in other
> stuff but it's still an aid).
> 
> Maybe we can do something like:
> 
> typedef enum _TnyError TnyError;
> enum _TnyError {
> TNY_ERROR_PERMISSION_DENIED,
> TNY_ERROR_CONNECTION_UNAVAILABLE,
> etc
> };
> 
> GError *tny_error_new (TnyError error_number, const gchar *msg, ...);
> 
> void tny_set_error(GError** err, TnyError error_number, const gchar*
> msg, ..);
> 
> both with variable arguments. Each TnyError will have associated an
> error string (defined for example into the .c file). The GError will
> include both this string and the one set by the user.
> 
> Just a proposal.

Sounds good. Can you work out the proposal on a wiki page? I'll add my
own ideas and remarks too of course.

I don't think we need to make this very complicated. GError style is
certainly good enough. We do have to make sure that we can language bind
this to a try { .. } catch (theerror) { .. } story on higher language
somehow (this usually isn't very difficult, but sometimes more difficult
to also automatically generate).



-- 
Philip Van Hoof, software developer
home: me at pvanhoof dot be 
gnome: pvanhoof at gnome dot org 
http://www.pvanhoof.be/blog