Re: [Vala] Generating bindings for non-GLib/GObject based API

[Abderrahim Kitouni <a kitouni gmail com>]

Hi,

2010/4/22 Michael Wild <themiwi users sourceforge net>:
> Hi all
>
> I am currently trying to generate bindings for a API which has some
> peculiarities which I can't seem to find any solution for.
>
> 1) Constructor function: Say I would like to use a C function as the constructor for a class (as e.g. 
> newwin is used in curses.vapi). However, that C function does not return the allocated and initialized 
> object in the return value, but as the first argument. The return value is an error code instead. How would 
> I handle this?
I don't understand this, does the function still alocate the instance,
or does it just initialize it?

> 2) Delegates: The C API defines a number of callback functions, most of which take some user-defined data 
> as an argument one registers along with the callback function. However, the user data is often neither the 
> first nor the last argument. How can I wrap this?
[CCode (instance_pos=)]
you can use things like 3.1 for "after the 3rd argument" and 3.9 for
"before the 4th argument"

> 3) Is there any comprehensive attributes reference somewhere? The Vala reference (draft version) doesn't 
> really say much, and actually seems to be quite a bit stale.

Some time ago, someone posted a "work in progress" here [1], not sure
if it has been added to the wiki or something.

Regards,
Abderrahim

[1] http://mail.gnome.org/archives/vala-list/2009-December/msg00019.html