Re: The new Boost 17.0.0

From: Dominique Devienne (ddevienne_at_[hidden])
Date: 2020-11-27 14:04:50

On Fri, Nov 27, 2020 at 12:56 PM Matt Borland via Boost <
boost_at_[hidden]> wrote:

> On Fri, 2020-11-27 at 11:58 +0300, Antony Polukhin via Boost wrote:
> > == The Solution
> > TL;DR: we need a C++17 fork of Boost with close to 0 dependencies
> > between libraries and namespace versioning.
>
> If I may propose another course of action for discussion what about a
> Boost 2.0 that is based on the C++20 standard? One of the goals of
> modules was to reduce compile times/overhead especially with monolithic
> libraries like boost. After a module has been imported one time it
> should be nearly free to use thereafter. [...]
> We could use the python 2/3 model where both are supported with a
> published countdown to when new development ceases on the old version.
>

Hi. I like that idea. I'm on C++17 and Boost 1.74, likely for a long time*,
so a C++17
Boost fork would work better for me, but C++20's modules and concepts do
seem
like a stronger base for a Boost 2.0 and would yield bigger bang for the
buck, longer term.

Boost 1.0 would remain, mostly as it is currently, with a wide range of
supported standards and compilers.
But a subset of Boost would be modularized and ported to C++20 and later,
taking full advantage of that much higher footing.

I also think Boost 2.0 should not try to work around buggy C++20 compilers
(and std-lib), and simply accept
that some advanced libraries won't work on non-conforming C++20 compilers.
Kinda like Boost.Hana didn't
try to work-around MSVC bugs of the past. Have Boost 2.0 look forward to
the future, and the next 10/20 years
while letting Boost 1.0 look back at the past 20 years (with still some
maintenance for the near future).
The analogy with Python2/3 is also a good one IMHO.

This is just wishful thinking of course. Maintainers may not want to port
to Boost 2.0 >= C++20 while still
maintaining Boost 1.0. I just think Boost needs a second breath, and a
clean reboot for the next decade.

FWIW, --DD

* Like many companies, we upgrade compilers and dependencies only every 2-3
years.