Re: Started adding GObject signals to gnome-class

[Alberto Ruiz <aruiz gnome org>]

This reminds me, pretty much nobody is subscribed to this list, adding
related parties to the discussion.

Please guys subscribe to this list!

2017-08-23 0:49 GMT+01:00 Alberto Ruiz <aruiz gnome org>:
> As per how to map G_TYPES, you should have a look at
> https://github.com/gtk-rs/glib/blob/master/src/types.rs as most of the
> work is done there. Specifically to the two last impls of the file.
>
> I do foresee some clashing between the work we're doing with
> gobject_gen and gtk-rs, eventually we'll need a roadmap to bring the
> two things together and being able to subclass from existing C
> GObjects and classes already bound by gtk-rs (say,
> Gtk.Application...).
>
> 2017-08-22 2:22 GMT+01:00 Federico Mena Quintero <federico gnome org>:
> > Dear rustaceans!
> >
> > Today I finally got off my ass and started adding GObject signals to
> > gnome-class.  You can see my progress here:
> >
> > https://github.com/federicomenaquintero/gnome-class
> >
> > So far I'm just getting familiar with the way gnome-class is
> > constructed.  I'm able to parse stuff like
> >
> >   gobject_gen! {
> >       class Foo {
> >           ...
> >           signal clicked(&self);
> >       }
> >   }
> >
> > and generate a completely non-functional call to g_signal_newv() inside
> > the generated class_init().
> >
> > I'm trying to define the appropriate syntax to declare signal flags;
> > I'll probably base it on Vala, which uses something like this:
> >
> >     [Signal (action=true, detailed=true, run=true, no_recurse=true, no_hooks=true)]
> >     public signal void sig_1 ();
> >
> > Some things which I don't know how to do yet:
> >
> > * Translate Rust types into G_TYPE_FOO equivalents, so that if there is
> > something like
> >
> >      signal bar (x: c_uint, y: &str;) -> c_uint;
> >
> > we'll generate the appropriate
> >
> >      g_signal_newv(...
> >                    G_TYPE_UINT, // return type
> >                    2,           // n_params
> >                    G_TYPE_UINT,
> >                    G_TYPE_STRING);
> >
> > I'd like to constrain the Rust types that get accepted to those that
> > are mappable to G_TYPE_*.  I have no idea how to say, "I can accept
> > GObjects of superclass GFooClass" - i.e. where to get the appropriate
> > GType value.  I also have no idea of how to declare new boxed types for
> > GObject, e.g. if we wanted to export a plain struct for a
> > GColor{r, g, b, a} or something similar.
> >
> > * How to remember the signal ids that g_signal_newv() generates, and
> > how to emit the signals later.  Niko has a clever mechanism so that the
> > generated code's internals use a number of traits and structs that are
> > only accessible from there.  I'd probably want to generate something
> > like
> >
> >   struct FooClassSignalIds {
> >       foo_signal_id: c_uint,
> >       bar_signal_id: c_uint,
> >       ...
> >   }
> >
> > and in class_init(), fill those out like
> >
> >   ids.foo_signal_id = g_signal_newv(...);
> >   ids.bar_signal_id = g_signal_newv(...);
> >
> > Also, as a replacement for g_signal_emitv(), which is tricky to call by
> > hand, maybe also have an
> >
> >   impl FooSignals for FooClass {
> >       fn emit_foo(&self, x: c_uint, y: &str) -> c_uint {
> >           g_signal_emitv(...);
> >       }
> >   }
> >
> > Then, the user's code would simply call
> >
> >   let r = self.emit_foo(42, "hello");
> >
> > or something.
> >
> > Does this seem sane?
> >
> > My main blocking point is how to translate Rust types into G_TYPE_* so
> > I can call g_signal_newv() with the type declarations it needs.
> >
> > I'm also open to suggestions on how to store the signal ids and how to
> > use them, although if that scheme of internal traits/structs works out,
> > it seems like it would be nice to use.
> >
> >   Federico
> > _______________________________________________
> > Rust-list mailing list
> > Rust-list gnome org
> > https://mail.gnome.org/mailman/listinfo/rust-list
>
>
>
> --
> Cheers,
> Alberto Ruiz



-- 
Cheers,
Alberto Ruiz