Re: [Boost-users] boost::range vs && (rvalue ref)

Subject: Re: [Boost-users] boost::range vs && (rvalue ref)
From: Thorsten Ottosen (thorsten.ottosen_at_[hidden])
Date: 2013-01-11 02:38:41

On 11-01-2013 04:37, Nathan Ridge wrote:
>
>> Passing range by ref (&) is fine, but using (&&) results in and error. Any
>> ideas?
>>
>> [snip]
>
>
> When you pass by T&&, the deduced type of T will include the reference.
> (So e.g. if you have a T&& argument and you pass in an int rvalue, T
> will be deduced as 'const int&'. If you pass an int lvalue, T will
> be deduced as 'int&'. This is in contrast to a regular reference, like
> T&, where if you pass an int lvalue, T will be deduced as just 'int').
>
> Range metafunctions don't accept references to range types as their
> input; you must pass the range type itself.
>
> So, you must call remove_reference<> on the deduced type 'T' prior to
> passing it to a range metafunction.
>
>
> I wonder if we should change the range metafunctions to accept
> references to range types, and do the reference stripping
> themselves?

I think we should. This has come up before.

-Thorsten