# The Rust Programming Language - The Rust Programming Language

## The Rust Programming Language

## [The Rust Programming Language](broken://pages/-MTSOW93Ydo7E0IvCQ-j#the-rust-programming-language)

*by Steve Klabnik and Carol Nichols, with contributions from the Rust Community*

This version of the text assumes you’re using Rust 1.48 or later with `edition="2018"` in *Cargo.toml* of all projects to use Rust 2018 Edition idioms. See the [“Installation” section of Chapter 1](https://doc.rust-lang.org/book/ch01-01-installation.html) to install or update Rust, and see the new [Appendix E](https://doc.rust-lang.org/book/appendix-05-editions.html) for information on editions.

The 2018 Edition of the Rust language includes a number of improvements that make Rust more ergonomic and easier to learn. This iteration of the book contains a number of changes to reflect those improvements:

* Chapter 7, “Managing Growing Projects with Packages, Crates, and Modules,” has been mostly rewritten. The module system and the way paths work in the 2018 Edition were made more consistent.
* Chapter 10 has new sections titled “Traits as Parameters” and “Returning Types that Implement Traits” that explain the new `impl Trait` syntax.
* Chapter 11 has a new section titled “Using `Result` in Tests” that shows how to write tests that use the `?` operator.
* The “Advanced Lifetimes” section in Chapter 19 was removed because compiler improvements have made the constructs in that section even rarer.
* The previous Appendix D, “Macros,” has been expanded to include procedural macros and was moved to the “Macros” section in Chapter 19.
* Appendix A, “Keywords,” also explains the new raw identifiers feature that enables code written in the 2015 Edition and the 2018 Edition to interoperate.
* Appendix D is now titled “Useful Development Tools” and covers recently released tools that help you write Rust code.
* We fixed a number of small errors and imprecise wording throughout the book. Thank you to the readers who reported them!

Note that any code in earlier iterations of *The Rust Programming Language* that compiled will continue to compile without `edition="2018"` in the project’s *Cargo.toml*, even as you update the Rust compiler version you’re using. That’s Rust’s backward compatibility guarantees at work!

The HTML format is available online at <https://doc.rust-lang.org/stable/book/> and offline with installations of Rust made with `rustup`; run `rustup docs --book` to open.

This text is available in [paperback and ebook format from No Starch Press](https://nostarch.com/rust).


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