On Wednesday, 10 October 2012 at 17:35:48 UTC, Jonathan M Davis
wrote:
On Wednesday, October 10, 2012 19:02:31 Zhenya wrote:
Hi!
I thought that this should compile:
class Foo{}
const(Foo) foo = new Foo;// the same that const Foo foo?
foo = new Foo;
but compiler say that foo is const reference and it can't
modify
it.
It is normally?If yes,how can I declare non-const reference to
const instance of class?
const Foo and const(Foo) are the same thing. They both create a
const
reference to const data. This is in contrast to a pointer where
const Bar* and
const(Bar)* are different. With a reference, there is no way to
indicate that
the object is const but not the reference. The type system just
doesn't
support the idea of a class object existing separately from a
reference, so
there's no way to make that distinction.
If you want to have a mutable reference to a const object, then
you need a
wrapper around the reference where the wrapper is mutable but
the reference
isn't. std.typecons.Rebindable does this. It's what you should
use.
- Jonathan M Davis
Thank you)
