Next const generics stabilisation

stephanemagnenat · August 31, 2021, 3:27pm

Const generics MVP was stabilised and released on March 25, 2021. This is a great and very helpful addition to Rust!

I was wondering whether there is a plan to add soon an incremental step for more const generics stabilisation. I am in particular thinking about enums, possibly only variants without arguments, which would be quite useful for replacing a set of int and would allow for exhaustive check in match.

Has anyone an update on that question? Thank you!

Luro02 · September 1, 2021, 12:26pm

github.com

lcnr/blog.rust-lang.org/blob/const-generics-update/posts/inside-rust/2021-09-01-Splitting-const-generics.md

---
layout: post
title: "Splitting the const generics features"
author: lcnr
description: "Splitting the const generics features"
team: The Const Generics Project Group <https://rust-lang.github.io/project-const-generics/>
---

After the stabilization of the const generics MVP in version 1.51, the const generics project group has continued to
work on const generics. Large parts of this work were gated behind the feature gates `const_generics` and `const_evaluatable_checked`. As time went on, the
`const_generics` feature became fairly useless on its own while the name of
`const_evaluatable_checked` didn't really capture what this feature was intended to do.

To improve this, we have removed the features `const_generics`, `lazy_normalization_consts`, and `const_evaluatable_checked` starting this nightly release. They have been replaced by `feature(adt_const_params)` and `feature(generic_const_exprs)`.

As there is a lot going on with const generics, here's a quick overview of the new - and preexisting - features and how much still needs to be done for them to get stabilized:

### `feature(adt_const_params)`

On stable, only integers, `char` and `bool` are allowed as the types of const parameters. This feature allows additional types, such as `&'static str` and user defined types.

This file has been truncated. show original

stephanemagnenat · September 1, 2021, 12:41pm

Great! Thank you very much for the update!

system · November 30, 2021, 12:41pm

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Next const generics stabilisation

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