This is the initial draft for support for standard versioning.

Much more work will follow if there is positive feedback from this initial draft.

The resulting work will be of a higher quality if the feedback is constructive.

WL

> On Sep 19, 2022, at 9:21 PM, William Linkmeyer <wlink10_at_[hidden]> wrote:
>
> 
> # Versioned Standard
>
> ### Document: <awaiting>
>
> ### Date: September 19, 2022
>
> ### Audience: LEWG
>
> ### Reply To: willhl_at_[hidden]
>
> ## Introduction
>
> ABI stability is a communication problem. Libraries, meant to be shared, often version themselves. The obvious purpose is to communicate change over time.
>
> The standard library itself is often versioned. Some shared standard library, `libc++.so.0`, may differ from some other shared standard library, `libc++.so.9`.
>
> There is no reliable channel of communication between between libraries and their associated standards.
>
> ## Motivation
>
> ABI is a perennial issue. Tools must be provided to users who wish to specify their intended standard library version.
>
> ## Implementation
>
> Introduce the *language* template to specify the intended standard version range to be used:
>
> ```c++
> using std = std::v<2017, 2023>;
> ```
>
> Which will embed an implementation-defined hint within the resulting binary.
>
> WL