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Subject: Re: [boost] [MPL lite or MPL 2] A modest proposal
From: Bruno Dutra (brunocodutra_at_[hidden])
Date: 2015-03-06 14:58:44

2015-03-06 15:13 GMT-03:00, Robert Ramey <ramey_at_[hidden]>:
> My proposal is a response to suggestions that we might address
> the mpl maintenance problem by eliminating support for older compilers
> and standards. In my opinion, the suggestion has merit in that writing mpl
> using C++11 features would result in something much easier to maintain
> and understand. Of course this would not be compatible with C++03 compilers.
> The only way to have it both ways is to leave the current MPL as it is
> and add a separately maintained "MPL Lite" or "MPL.core" or whatever
> which would be C++11+ only. For those who are concerned about the
> maintainability issue with the current MPL - and actually would be
> interested
> in doing something about it - I believe that this would be a good way
> forward.
> Of course the original MPL would be around as long as anyone needs it.
> This is my attempt to suggest something which pleases everyone.

No doubt support to defective compilers essentially renders MPL
unmaintainable. The only thing of which I'm not so convinced yet, is
the notion that keeping compatibility with C++98/03 would be that
harmful to maintainability. I still believe it could be managed and,
to me, that would be the perfect balance between compatibility and
maintainability, hopefully attracting maintainers to MPL(2) once

2015-03-06 15:30 GMT-03:00, Andrey Semashev <andrey.semashev_at_[hidden]>:
> I think the main question is if that's actually needed. The current MPL
> works
> on all compilers, old and new ones. There are little to no maintenance
> requests.

Users are still interested in maintaining MPL, as one may see by the
handful of bug reports issued in the past 5+ years, the problem has
just been finding someone to tackle them. I'm afraid many other bugs
might not have been reported for the simple fact users might feel they
won't be addressed, just like previous ones haven't still after so
many years.

As an example, just recently I decided to try addressing some of these
bugs and indeed got some feedback from a few maintainers, but I'm
still to find someone feeling confident enough with her/his knowledge
of MPL to review my pull requests. I find it of grave concern to have
such a core library left unmaintained, so, yes, I think it is needed.

*Bruno C. O. Dutra*

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