Re: [boost] [Concepts] Definition. Was [GSoC] [Boost.Hana] Formal review request

Subject: Re: [boost] [Concepts] Definition. Was [GSoC] [Boost.Hana] Formal review request
From: Krzysztof Czainski (1czajnik_at_[hidden])
Date: 2014-08-05 04:30:09

2014-08-05 6:33 GMT+02:00 Michael Shepanski <mps_at_[hidden]>:

> On 5/08/2014 1:39 AM, Roland Bock wrote:
>
>> On 2014-08-04 13:32, Mostafa wrote:
>>
>>> Concepts are sets of types
>>>
>> I think you are mistaken. A concept is a set of requirements,
>>
>
> I am under a New Year's resolution not to start philosophical arguments,
> but this one has already begun, so ...
>

Please don't forget, that not all requirements can be checked at compile
time. For example: TotallyOrdered. Just by checking, that an expression
(a<b) is valid and yields something boolable, you can't distinguish between
TotallyOrdered, PartiallyOrdered, or maybe neiter.

So, while I think it doesn't matter, whether we view concepts as sets of
types or requirements, I'd like to support this sentence of Mostafa:
"I view concepts not as a programmatic tool but as a communication tool for
conveying programmer intent."

Cheers,
Kris