Re: [Boost-users] Runtime identity

Subject: Re: [Boost-users] Runtime identity
From: Francesco Biscani (bluescarni_at_[hidden])
Date: 2010-12-01 15:12:39

On Wed, Dec 1, 2010 at 12:48 AM, John B. Turpish <jbturp_at_[hidden]> wrote:
> On Tue, Nov 30, 2010 at 10:06 AM, Robert Jones <robertgbjones_at_[hidden]> wrote:
>> Something that just returns it's single argument, eg.,
>>
>> template <typename T> T identity( T t ) { return t; }
> ...
>> (I need this because I need to pass a function object which simply returns
>> an
>> object I already have - maybe I've missed a more obvious method?)
>
> The way you wrote it, wouldn't that actually return a temporary that
> is a copy of the object you already have? (rather than a const T& or
> something)

I guess most compilers would apply some form of elision/return value
optimization?

Cheers,

  F.