Re: [Boost-users] [Proto] typeof in Hello World example

Subject: Re: [Boost-users] [Proto] typeof in Hello World example
From: Eric Niebler (eric_at_[hidden])
Date: 2010-11-15 16:47:51

On 11/15/2010 11:33 AM, Hossein Haeri wrote:
> Dear Eric,
> 
>> No, it belongs there for portability, but it is not needed on all 
>> compilers. Some older compilers don't have a decltype, typeof or 
>> __typeof__ operator. On those compilers, types need to be
>> registered with the Boost.Typeof library, which provides
>> emulation.
> 
> So, which part of the code will need this, could you explain? And, I
> would also suggest that you add the same explanation -- perhaps in
> the form of a footnote -- to the user guide.

The proto::_default transform needs typeof (built-in or emulated) to
know type type of an expression, so it knows what to return.

Good idea about the users' guide.

-- 
Eric Niebler
BoostPro Computing
http://www.boostpro.com