How will we fix opEquals?

[Jonathan M Davis]

On Thursday 10 February 2011 21:50:45 so wrote:
> > We _must_ have it there, so anyone overriding those functions _must_
> > use it for those functions. They could create non-const versions in
> > addition to
> > the const ones,
> 
> It is the whole point, they can't.

Hmm. You're right (I just tried it). I was certain that you could. It's the kind 
of thing that you could do in C++, but I guess that D is pickier about 
overriding. You can certainly _add_ const, but I guess you can't take it away 
even if there's also a const version defined. I guess that part of the problem is 
that I so rarely use classes in D. I usually use structs. I'm sure that will 
change if I ever get the chance to write large programs in D, but until I can 
use it at work I'm not sure how likely that is.

Well, then there's no caching of toHash unless you call a separate function to 
calculate and cache the result first, or you use a global variable to hold the 
cached value. That kind of sucks, but I think that const is far more valuable 
that the possibility of caching, and there _are_ ways to get the caching 
behavior in spite of const - they just aren't all that nice.

- Jonathan M Davis