On 04/26/2010 03:56 PM, Steve Schveighoffer wrote:
> Sorry, but that's not a reason.  Can you point to specifics?  The only reason I can think of is that C++ const is not transitive...

It's a long story. Binding rvalues to const references was a bad move that rvalue references are still trying to fix.

In D, we have enough of a hole by allowing rvalue objects to bind to ref. Let's not widen that.

Fundamentally, a ref originates from an lvalue with an identity and a place in memory. An rvalue is not quite all that. That's in short why binding an rvalue to a reference is fraught with peril: you are weakening what ref really means.

> How does auto ref solve the problem?

auto ref hits the spot. It means "I'm ok whether this data is an rvalue or an lvalue".


Andrei