Future of boost::TypeTraits

From: Gero Peterhoff (g.peterhoff_at_[hidden])
Date: 2023-02-24 18:16:07

Hello,
with the planned changes of the dependencies of the boost libraries to newer C++-standards, I would like to ask how this is planned for boost::TypeTraits.

1)
In my opinion it would make sense to remove all TypeTraits that are already in the standard, and only provide those that do not exist in the standard (yet). Of course, this depends on the planned minimum standard for boost::TypeTraits.

2)
If, on the other hand, boost::TypeTraits is to continue to work with C++03 (for which there may be reasons), however, quite a few adjustments must be made (for newer C++-standards) and bugs must be fixed. Examples:
a)
- no inline-variables are provided for C++17 (if useful), e.g. is_arithmetic_v
- no concepts are provided for C++20 (if useful), e.g. arithmetic - that's why I already asked how to do this best without coming into (name)conflicts with existing structures/namespaces/etc.
b) bugs
- e.g. is_integral does not contain char8_t (if available)


Probably my remarks also apply to other libraries, possibly TypeErasure, TypeIndex, TTI ...
All this has to be reworked fundamentally and consolidated if necessary.


best regards
Gero