What Are Rust Editions (2015, 2018, 2021, 2024)?

Rust editions are versioned snapshots of the language that allow the compiler to adopt new features and syntax without breaking existing code. You specify the edition in your Cargo.toml file under the [package] section to control which language rules apply to your project.

[package]
name = "my-project"
version = "0.1.0"
edition = "2021"

The available editions are 2015, 2018, 2021, and 2024, with 2021 being the current stable default and 2024 introducing further improvements.

Rust editions are like different rulebooks for the language that get updated every few years to include new features. By picking an edition in your project settings, you tell the compiler which set of rules to follow so your code works correctly. Think of it like choosing which version of a game's rules to play; everyone needs to agree on the same version to play together.