Exporting file completion routines

[Hrvoje Niksic <hniksic srce hr>]

Wouldn't it be nice if Gtk exported its file completion routines, so
that programs that want to implement file completion in its text-entry 
widgets can use them?  For example, GQmpeg has a `tabcomp.c' file
that exports a tab_completion_add_to_entry() function, allowing you to 
easily add completion to your text entries.

The interface to the completion could be separated into a special
file, with a convenience function, say:

    void gtk_text_entry_add_completion(GtkWidget *entry,
                                       void (*enter_func)(gchar *, gpointer),
                                       gpointer data)

Have other plans to implement this been proposed?  Any comments?