On 9/29/11 8:38 AM, Steven Schveighoffer wrote:
On Thu, 29 Sep 2011 11:09:13 -0400, Christophe
<trav...@phare.normalesup.org> wrote:
"Steven Schveighoffer" , dans le message (digitalmars.D:145738), a
It is always possible for a non-const version of opEqual to forward to
the const version, so people willing to use a const version do not have
to define a non-const version.
Again, you still need to define both, this is not a good situation.
No, I didn't express myself correctly. The non-const version should
forward to the const version *by default*.
Fine, but if you want to define a non-const version that *doesn't* call
the const version, you have to define both. So even if you *don't* want
to deal with const, you still do. I should have been clearer, sorry.
Note that the compiler currently calls a global method which accepts two
non-const Objects. In order for it to support both const and mutable
versions, it would have to have 4 different functions.
I really don't think all this complexity is worth the benefit. Just
learn to use const properly, or don't use the operator system to do
comparisons. Object.opEquals should be const.
If we make this change we're liable to break all code that defines
opEquals for classes.
Two versions should be enough: const/const and mutable/mutable, which by
default forwards to const/const. Old code will run unchanged at a slight
efficiency cost due to forwarding. Since it didn't previously work for
const anyway, no harm done.
New code gets to only override the const/const version.
Where is this wrong?
Andrei