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Subject: Re: [boost] Hana Typeclass
From: Niall Douglas (s_sourceforge_at_[hidden])
Date: 2014-08-03 16:42:40

On 3 Aug 2014 at 11:32, Robert Ramey wrote:

> To me the "type class" of the Hana library is a muddled re-implemenation of
> the boost concept check library. Its much more complicated and subtle and
> not as well documented and doesn't add anything to BCC.

You probably didn't mean to Robert, but that review came across as
mean spirited. I'm going to assume you didn't mean it that way, the
same way you didn't mean it that way when you hassled Paul, also a
GSoC student by the way, in his C++ Now presentation about porting
AFIO to Boost.

Hana is different. This student engineer new to Boost and the way
things are done here has tried to break new ground and do new stuff
which demonstrates the power delivered by C++ 14 compilers. He's
taken a very Haskell-y route, right down to the un-C++ terminology
and not using STL idioms, but then so what if he has? The STL is an
ancient legacy design, it may be time to diverge drastically, or it
may not.

I have no idea if what he's done or how he's done it is the best
approach - I'm not competent in this area like Eric or Joel is. But
how he went about the prior art research, the benchmarking of all
implementation approaches, the presentation of his work at C++ Now
before proceeding with implementation, all of this bodes extremely
well indeed. Whatever he has done, it isn't going to be ill judged
and muddled, that's for sure.

Hana isn't BCC. It's far more - it's potentially a hint of how C++ in
the 2020s could look like, which hopefully is not how things are
currently done right now. I hope that the Boost culture is still able
to welcome radically new ideas and new engineers and stride forth
instead of this constant defence of the (ancient) past and its way of
doing things as if we're losing something vital other than our
membership, which if I can remind you, has been dropping for two
years now.


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