Re: [boost] [gsoc-2013] Boost.Expected

Subject: Re: [boost] [gsoc-2013] Boost.Expected
From: Vicente J. Botet Escriba (vicente.botet_at_[hidden])
Date: 2013-04-20 05:36:52

Le 20/04/13 10:50, Vicente J. Botet Escriba a écrit :
> Le 19/04/13 16:36, Pierre T. a écrit :
>> On 04/13/2013 12:57 PM, Klaim - Joël Lamotte wrote:
>>> On Sat, Apr 13, 2013 at 8:38 AM, Pierre T. <ptalbot_at_[hidden]> wrote:
>>>
>>>
>> Hello,
>>
>> I gave a try at the implementation of the expected_or_error class.
>> I used the boost layout to package the implementation, you can 
>> download it here : http://www.hyc.io/boost/expected.zip
>> Finally, feel free to explore the documentation I wrote 
>> http://www.hyc.io/boost/index.html
>>
>> Please, do not hesitate to give me advices and critics to improve 
>> this library and my future proposal.
>>
>>
> Hi,
>
> glad to see you are exploring the different alternatives. This is 
> really a good starting point.
>
> Now it is time to make a concrete proposal for you candidature.
>
>

Hi again,

I have some questions:

Do you think that expected and/or expected_or_error could/should have 
value semantics, that is define operator==?
I don't know if the const get function should be provided?
   const T& get() const { return value; }
what do you think?

What about an explicit conversion to the underlying type that behaves as 
the get function?
What about an explicit conversion to bool that behaves as the valid 
function?
Do you pretend to provide a C++98 portable implementation?
How the expected_or_error behaves in the presence of copy constructor 
exceptions?
Which expected_or_error<> functions can be declared as noexcept?
Which expected<> functions can be declared as noexcept?

Best,
Vicente