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Subject: [boost] c++03 library survey
From: Mike Dev (mike.dev_at_[hidden])
Date: 2018-08-28 11:37:06

Hello everyone,

this is closely related to the thread about "A possible date for
dropping c++03 support" (!topic/boost-developers-archive/i4UM-GfNu8w),
but this is NOT meant as a vote on the suggestion, and I'd ask
you to keep discussions to that thread. For the actually important
part, please scroll down to the double line (===)

For reference however, my suggestion was that c++03 support
is officially dropped somewhere around early 2020 across all
of boost. Which would mean, that from then onwards any library
author could start to unconditionally use c++11 features in
his library without prior announcement or transition period,
even if other boost libraries that currently support c++03
have a dependency on it.
(Again, if you have questions or comments about this, please
answer on the other thread)

Somewhat late, I realized I first should have asked if / how
much actual interest there is from the side of the library
maintainers in the first place, because whatever the majority
of the people on the ML thinks, it obviously won't have any
effect if the actually affected people don't have any interest
in using c++11 in the first place.

Full disclosure: I'm not a boost contributor myself (at least
nothing significant) but as a user, I have an interest in boost
libraries becoming simpler, less entangled with each other and
providing less types that are redundant in c++11 and later.
You could call that more lightweight but that is a different
So, to get some idea if there is any interest in this topic,
I'd ask each maintainer that is currently maintaining a c++03
compatible library to answer the following questions:

=======Please quote from here ======================================

- Which library/ies are you maintaining? (I assume this isn't some
  sort of private information - otherwise ignore the question)

- Would you like to unconditionally use c++11 features if you would
  not have to worry about this breaking boost internal users?

- Would you like to unconditionally use c++11 features if you would
  not have to worry about this breaking any users?

- Would you deprecate your library completely if there were no
  boost-internal users and your current dependencies required
  c++11 (e.g. because your library has been merged into the c++11
  standard library anyway)

- Are you yourself using any boost library (in an up-to-date version)
  in a c++03, non-boost project?
- Do you have any Idea if the latest versions of your library is
  used by any important/significant number of c++02 projects?
  [It is only important if *you* consider those projects important
   and or the number significant]

=======Please quote till here ======================================

Note: When I'm talking about breaking users I mean breaking due to
requiring c++11 compiler, not because you completely rewrite the API
based on new c++11 idoms - that would probably better be done in a
completely new library.

Best regards and thank you for your time


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