Re: debug flags and g_type_init()

[Tim Janik <timj gtk org>]

On 5 Jun 2001, Owen Taylor wrote:

> 
> Currently:
> 
>  - g_type_init() can be called multiple times
>  - debug flags not set the first time will be silently ignored.
> 
> So, in the rare case that someone wants to set the debug
> flags, they have to do:
> 
>  g_type_init (my_debug_flags);
> 
>  gtk_init (&argc, &argv);

right, unless they want debug flags parsed by gtk_init() take effect.

> Why not remove the debug flags argument to g_type_init()
> and have a separate g_type_set_debug_flags()? This has
> the advantages:
> 
>  - We omit the mysterious 0 from g_type_init(0)
>  - We can put out a meaningful error if someone tries to 
>    set the debug flags after GType is initialized.

it also has disadvantages:

a) things break if _g_type_debug_flags is evaluated after
   g_type_init() but before g_type_set_debug_flags() (currently
   this will be triggered when initializing the gobject class).
   for the future, we might even have per type-node debug info,
   at that point debug flags have to be known right at g_type_init()
   time (that's because g_type_init() already creates a couple type
   nodes)
b) g_type_set_debug_flags() is yet another special function for the
   user to remember, to call _before_ any other function, together
   with (a), up to the extend of having to call g_type_set_debug_flags()
   even before g_type_init()
c) not considering (a), your approach will cause the type system to
   puke upon gtk_init() if the user enabled certain debugging beforehand

i don't think we can do much about not silently ignoring subsequent debug
settings, unless we introduce something like g_type_is_initialized() which
i think is taking the issue a bit to far.
if people really dislike the "mysterious" 0 to g_type_init, we could
however change things towards:

void g_type_init                (void);
void g_type_init_with_debugging (GTypeDebugFlags debug_flags);

both would still have to be silent upon subsequent invokations however.

> 
> Regards,
>                                         Owen
> 
> 

---
ciaoTJ