Re: [boost] [multiprecision] Some rvalue reference experiments (performance inhancements #1)

Subject: Re: [boost] [multiprecision] Some rvalue reference experiments (performance inhancements #1)
From: Marc Glisse (marc.glisse_at_[hidden])
Date: 2012-06-30 13:17:22

On Sat, 30 Jun 2012, John Maddock wrote:

> I've started to work through some of the points that came up in the 
> multiprecision review, starting with further rvalue reference support.
>
> The idea (due to Marc Glisse) was to add operator overloads that look 
> something like:
>
> Number&& operator+(Number&&a, const Number& b)
> {
>  return static_cast<Number&&>(a += b);
> }

The safe solution is returning Number, not Number&&. If Dave reads this 
message, he can probably point us to previous discussions about this. 
Being able to return Number&& would be great...

Note that changing the return type from Number&& to Number cancels the 
allocation gain when using a type like GMP that doesn't have an empty 
state.

-- 
Marc Glisse