Re: [boost] [Hana] Formal review

Subject: Re: [boost] [Hana] Formal review
From: Glen Fernandes (glen.fernandes_at_[hidden])
Date: 2015-06-18 13:20:39

Every reviewer and contributor to this discussion is, of course, entitled
to their view of:
- What makes a library useful (including how many compilers are supported)?
- What the standard for Boost libraries should be (minimum compiler
support)?

While it is may be beneficial to discuss those two questions above (perhaps
even independent of Hana's review, for all of Boost, and with a different
subject), I just want to make certain that nobody is under the impression
that Hana is ineligible for review because of compiler support.

Here is my take on it:
1. The current requirements for Boost libraries do advise authors of
only:[1]
    a. "Aim for ISO Standard C++"
    b. "There is no requirement that a library run on C++ compilers which
do not conform to the ISO standard."
    c. "There is no requirement that a library run on any particular C++
compiler. Boost contributors often try to ensure their libraries work with
popular compilers."

2. Compiler vendors today are more actively trying to conform to the
standard. In my mind it is a question of "when" g++ will support the
necessary features, not "if". These aren't contentious things that anyone
is concerned will never be supported. (e.g. It is not like we're back in
2003 and someone has submitted a library that is littered with
unconditional use of the 'export' keyword).

3. Usefulness is more important that [current] compiler support. If
[future] g++ 5.3 and clang 3.5 users get to enjoy useful libraries, these
libraries can drive language conformance in other compiler vendors. (Useful
and popular Boost libraries driving minimum C++ language feature support in
compiler vendors is also an appealing thought).

Glen

[1] http://www.boost.org/development/requirements.html