Many C++ people like shallow copy things to explicitly have a pointer-like syntax. I, personally, can happily tolerate either.
For an apples to apples comparison,
window w("Example window");
should be compared with
window w = create_window("Example window");
Shrug. I'm not a GUI person, in large part because every time I look into it, I end up deciding that it's far more work to learn how to use than the benefits would justify. A boost-supported cross platform GUI would definitely go far in addressing the issue of not wanting to invest time learning something which is largely tied to a single platform. But what I'd really like to see is a system that allows one to accomplish conceptually simple things in a correspondingly simple way, with sensible default behavior of any aspects which aren't explicitly specified and a minimum of exposed implementation details to contend with. While window may very well be implemented as a pointer, I don't see how that fact should be relevant to the user of the library (other than, I suspect, historical antecedents). Of course, I understand that I'm an atypical programmer in that the bulk of my code is written solely for my own use or the use of other scientists rather than end users, and a GUI would be nice but is nonessential.
w.wait_for( delete_signal() );
just introduces a redundant top-level tag class and a corresponding redundant window_base overload.
I would be willing to sacrifice added complexity of implementation to have a more intuitive syntax. Unless I'm reading this wrong, what wait_for_signal(w->delete_signal) is trying to say is that w should wait for a generic delete signal - that is, delete_signal isn't really something that belongs to the window type but is instead an abstract directive to a window (or button or widget or whatever) to delete itself. What it actually says to me, on reading it, is that the main program is waiting for a signal from w to quit running. Anyway, bear in mind that this is all coming from a computational physicist with no real experience in GUI programming who'd love to see something simple and intuitive appear. ------------------------------------------------------------------------ --------------------------- Matthias Schabel, Ph.D. Utah Center for Advanced Imaging Research 729 Arapeen Drive Salt Lake City, UT 84108 801-587-9413 (work) 801-585-3592 (fax) 801-706-5760 (cell) 801-484-0811 (home) mschabel at ucair med utah edu