Re: Dropping C++03 support (again)

From: Gavin Lambert (boost_at_[hidden])
Date: 2023-02-20 06:23:44

On 20/02/2023 12:00, Andrey Semashev wrote:
> Regardless of the intention, this isn't a license to break existing
> code. There are reasons to keep using Boost.Operators in C++20 and
> beyond - one of them being compatibility with prior C++ versions.

Sure, but in theory Boost.Operators classes could just switch to a 
simplified implementation when C++20 is in use.

Perhaps there are some cases that become tricky to map from one to the 
other, but less_than_comparable naturally maps to spaceship and 
equality_comparable happens for free, and most of the others shouldn't 
be affected, I would have thought?

> Sometimes it seems the Committee just assumes the world will momentarily
> upgrade to the latest C++ standard and all legacy code cease to exist.

I don't think this is true; it's a long-standing joke that all of the 
default behaviours of C++ are wrong, in order to maintain backwards 
compatibility of legacy code.  (See also: explicit, [[nodiscard]].)

As someone who maintains a 40+-year-old codebase myself, I'm quite 
thankful that code in the dark recesses still mostly works without 
having to disturb the spiders.