[Vala] Question about GHashTable-style foreach

["W. Michael Petullo" <mike flyn org>]

I am having trouble with Vala and a GHashTable-style foreach. I have
created a Vala API for my library, which defines an interface with a
GHashTable-style foreach method. Vapigen / my Vala API file defines
this as:

public abstract void @foreach(GLib.HFunc func, void *data)

When I define a method in Vala as follows, I end up with an extra argument
in the generated C source:

public void @foreach (GLib.HFunc func, void *data) {...}

generates:

static void class_real_foreach (DMAPDb* base, GHFunc func,
                                void* func_target, void* data) {...}

and fails to compile (note the two "user_data" parameters: func_target
and data).

When I remove the "void *data" from the Vala code (and Vala API file),
everything compiles fine. However, the generated C code contains calls
such as the following:

dmap_db_foreach ((DMAPDb*) self->priv->db,
                 (GHFunc) dpap_viewer_render_record, NULL);

So, the parameter passed as "user_data" is NULL. But, I need to pass
something. What am I doing wrong?

-- 
Mike

:wq