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Subject: Re: [boost] [GSoC][MPL11] Post C++Now update
From: Louis Dionne (ldionne.2_at_[hidden])
Date: 2014-05-19 13:59:13

Joel de Guzman <djowel <at>> writes:

> On 5/19/14, 9:11 PM, Zach Laine wrote:
> > [...]
> >
> > That being said, it doesn't look like Louis is committed to one approach or
> > another yet; he is still investigating. Also, he is not committed to
> > making a drop-in Fusion replacement, just an updated MPL for C++11/14. He
> > is simply trying to incorporate Fusion-like elements in that where they are
> > appropriate. Louis, please correct me if I'm mistaken.

That's correct. I'm just trying to figure whether it is possible/desirable
to have a universal metaprogramming library for C++.

Also, there are no plans to build a drop-in replacement for Fusion. Whatever
I come up with won't be backward compatible with Fusion because it won't use
iterators, which I consider as a design flaw. It won't be backward compatible
with the MPL for the same reason.

> Sounds very cool. I'd love to see a proof of concept toy example. Anyone?
> My concern here is that constexpr has severe limitations. I wonder
> how useful a fusion library based on constexpr will be.

Louis Dionne

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