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Subject: Re: [boost] [GSOC] Mentors for a C++11 TMP-related project
From: Niall Douglas (s_sourceforge_at_[hidden])
Date: 2014-03-08 13:29:41

On 8 Mar 2014 at 16:58, Louis Dionne wrote:

> I would like to know if someone is interested to mentor a project
> whose aim is boldly to:
> - Document the current state of the art in C++11 template metaprogramming.

Replace "Document" with "Review" and I think Google will be happier.
They don't fund writing literature reviews.

> - Propose modifications to the current Boost.MPL or perhaps write a TMP
> library as a successor to the MPL.

You'll need to be more concrete for GSoC. Explicit work items e.g.
replacing all faux variadic templates with real variadic templates.

> I have been working on a C++11 TMP library[1] for a while now, and I will
> present the state of my work at C++Now 2014. In the process of writing
> the library, I experiment with several TMP techniques, which I document
> and benchmark. The goal is to propose a new library that improves over
> the current MPL in a measurable way (i.e. it's not just my preference).
> That library could be seen as a C++11 successor to the MPL and new
> code could use that instead of the MPL.

I think I am not alone in considering your presentation at C++ Now
2014 to be a must see. The two other people presenting same slot as
you (provisional) are very strong and talking on important topics,
but yours I think will be the most popular for library writers.

> (1) Input is negative enough that the idea to propose it is dropped. In that
> case, I could work on improvements to the current MPL during the summer.
> The kind of improvements I'm talking about range from documentation to
> bugfixes to support for C++11 when available.
> (2) Input is generally positive and the library is proposed circa the
> beginning of the summer. If the library is refused, then I'm back to (1).
> Otherwise, I can work on improvements and modifications required for the
> library to officially make it in.
> In both cases, the scope of the project seems reasonable to me.

Your mentor and you can decide anything for GSoC, even something very
controversial. Obviously you need the Boost community to rank your
proposal highly, but if say you get a member of the Boost steering
committee to mentor you, I would doubt anyone would rank such a
proposal poorly. After all, you have written actual implementation
code which proves you've thought about the problem deeply, and that
puts you way ahead of most other candidates.

I haven't looked at your MPL11 replacement library closely enough to
say whether it's a good replacement for MPL. My personal single
biggest concern is that I think you need Concepts in the language
before an MPL replacement can really fly, and that probably removes
Visual Studio from available compilers which is a showstopper. I
certainly am looking forward hugely to your C++ Now presentation to
learn more.

> There is nothing similar in the list of proposed GSOC projects, so if
> someone is interested in mentoring this project, please speak up. I
> will then go through the normal process for proposing GSOC projects
> and include a more detailed description of it, and we'll see what happens.

I think you need to get a suitable mentor before all else, but if you
do, I'd say your golden.


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