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Subject: [boost] [metal] Feature Complete - Request for Feedback
From: Bruno Dutra (brunocodutra_at_[hidden])
Date: 2017-02-20 20:49:17

Dear community,

As some of you might be aware through sporadic discussions on this mailing
list throughout the last couple of years, I've been working for quite a
while on a modern template metaprogramming library called Metal, that I
advocate as a direct replacement for the aging Boost.MPL.

I believe my work is finally complete now and so I come to you to request
for feedback and ask whether you think that Metal would be a valuable
addition to the Boost distribution. My intention is to request a formal
review in the next days / weeks, depending on your preliminary feedback.

In a glimpse, Metal is a pure template metaprogramming that explores all
modern features available to C++14 to overcome the limitations of
Boost.MPL, most notably:

* vastly improved performance [1];
* terser syntax [2].

Boost Incubator:

I appreciate your feedback and opinion on whether Metal is a good fit for

- Previous discussions

About a year ago I came to this list to discuss a proposal of merging Metal
into MPL as a new API built from ground up, while at the same time serving
as a backend for the previous API on modern compilers.

At that time, Metal was lazy and very similar to MPL, but since then it
underwent great simplification and embraced the all-eager design, so I
don't think this would be a good idea anymore. Besides, it soon became
clear that this would be a huge undertaking with potential to inadvertently
breaking a lot of good code to little gain,
so I decided instead to tackle the problem migration from MPL by providing
a handy adaptor [3].


Bruno Dutra

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