Abstract
The talk aims to introduce the `#[diagnostic]` attribute namespace. This new tool namespace allows to hint the Rust compiler to emit a specific error message text in certain situations. It's meant to help crate authors to take control over error messages emitted by the compiler that occur while upholding certain domain specific compile time constraints. The feature was stablized with Rust 1.78.
Beside introducing this new feature, I would like to use this talk to go through the process of designing, implementing and stabilising such a new language feature. I hope that the proposed talk can encourage people to contribute to the compiler itself by showing how to approach specific steps of the design and implementation process.
Disclaimer: I'm neither part of a relevant Rust team nor would I speak in a official compiler related role.
