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Subject: Re: [boost] Interest in a Boost.Chrono/Date library
From: Philip Bennefall (philip_at_[hidden])
Date: 2015-10-25 13:30:02

On 10/25/2015 5:51 PM, Vicente J. Botet Escriba wrote:
> Hi,
> maybe some of you have already see the Howard Hinnant presentation at
> CppCOn2015 [1] about his new data-v2 library [2]. My prototype of
> Boost.Chrono/Date library ([3] ] was based on the Howard original
> library, but when we want to reach the maximum of performances we need
> to use a specific date class for each usage. This is what Howard
> explains in his marvelous presentation ans his tiny date library
> My post here wants to know if there is interest in a library providing
> what H.H. date library provides in Boost.
> Note that his data-v2 library yet doesn't provides as much as
> Boost.Date provides but IMHO it is much elegant and efficient. If
> there is enough interest, I will request you to do a first review of
> the H.H. Date-V2 library.
> Then once we have a consensus I will make my POC Chrono/Date library
> ready for review.
> H.H. Date-V2 is under MIT license, which IIRC is compatible with the
> Boost license. I don't know yet if would need to add this license, as
> my POC [3] is already a good starting point, nevertheless, I would
> like to know if there could be any issues about having the source
> under both licenses.
> Best,
> Vicente

Hi Vicente,

Personally I would be very interested, however while I'm not a lawyer I
see what I think might be an incompatibility or at least a point which
raises ambiguity between the Boost license and the MIT license. The
Boost license clearly states that binary distributions of derivative
works do not require attribution in the documentation, while the MIT
license is unclear on this as far as I can tell.

The relevant portion of the MIT license is:

The above copyright notice and this permission notice shall be included in
  all copies or substantial portions of the Software.

It is not clear to me what "all copies or substantial portions of the
Software" means. The original source package? Derivative works in source
code form? Compiled derivative works? A bit of googling gives me
conflicting information but most people seem to think that it refers to
compiled derivative works as well, which is incompatible with the Boost
license if this is indeed the correct interpretation of the MIT license.

Kind regards,

Philip Bennefall

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