Re: GLib/perl and GArray, GType

[muppet <scott asofyet org>]

On Dec 11, 2008, at 9:47 AM, Wouter Verhelst wrote:

> On Thu, Dec 11, 2008 at 12:31:09AM -0500, muppet wrote:

> > Now, it's fairly easy for you to create a function that knows how to
> > convert an array of whatever, and create a typemap for that.  Then  
> > you
> > can use that all over the place in your own code.
>
> Sounds like that could work. Having said that, I've not done much XS
> code beyond this project, and since your code has generated all my
> typemaps there (thanks, BTW), I wouldn't know where to start. Care to
> give me a pointer? ;-)

Clue * clue_p = &a_big_clue;

[Okay, that was a horrible joke, i have to admit.]

The easiest would be to use typedef to create aliases for arrays and  
lists, so as to reflect their contents and give them unique symbols.

typedef GList * FooListOfGtkWidget

Then, in the file typemap, you can associate type mapping code with  
the typedef:

TYPEMAP
FooListOfWidgets        T_LIST_OF_WIDGET

INPUT
T_LIST_OF_WIDGET
        $var = av_to_glist_of_widget ($arg);

OUTPUT
T_LIST_OF_WIDGET
        $arg = av_from_glist_of_widget ($var);

You can also get really cute and try to infer the type name from the  
$var and $arg variables, as with T_GPERL_GENERIC_WRAPPER.  There's  
more information on this in L<perlxstut>.


> > I had knocked together a patch that implements this, but working the
> > kinks out of value coercion in the unit test expanded to fill all my
> > available time for the evening, which was about half an hour.  :- 
> > (   I'll
> > try to get you a working patch later this week.
>
> That'd be great, thanks; and if you don't make it this week, there's  
> no
> rush -- I know what's going on, and this is (mostly) a hobby project
> anyway.


I seem to be misunderstanding the GParamSpecGType docs when they talk  
about how is_a_type works when it's G_TYPE_NONE.  So, the unit test is  
a bit incomplete, and i can't guarantee that this works as intended.   
Please try it out and let me know what you think.  The patch is  
against SVN trunk HEAD, but should be easy to apply to a recent  
release -- not much has actually changed in these parts.

Attachment: GParamSpecGType.patch
Description: Binary data

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