The Rust Release Team - Announcing Rust 1.40.0 (Highlights)

# The Rust Release Team - Announcing Rust 1.40.0 (Highlights) ![rw-book-cover|256](https://readwise-assets.s3.amazonaws.com/static/images/article4.6bc1851654a0.png) ## Highlights - Option::flatten - `#[non_exhaustive]` structs, enums, and variants