The Rust Project Developpers - The Rust Programming Language

This first chapter of the book will get us going with Rust and its tooling. First, well install Rust. Then, the classic Hello World program. Finally, well talk about Cargo, Rusts build system and package manager.

Well be showing off a number of commands using a terminal, and those lines all start with $. You dont need to type in the $s, they are there to indicate the start of each command. Well see many tutorials and examples around the web that follow this convention: $ for commands run as our regular user, and # for commands we should be running as an administrator.

The first step to using Rust is to install it. Generally speaking, youll need an Internet connection to run the commands in this section, as well be downloading Rust from the Internet.

The Rust compiler runs on, and compiles to, a great number of platforms, but is best supported on Linux, Mac, and Windows, on the x86 and x86-64 CPU architecture. There are official builds of the Rust compiler and standard library for these platforms and more. For full details on Rust platform support see the website.

All you need to do on Unix systems like Linux and macOS is open a terminal and type this:

$ curl https:// sh .rustup.rs -sSf | sh

It will download a script, and start the installation. If everything goes well, youll see this appear:

Rust is installed now. Great!

Installing on Windows is nearly as easy: download and run rustup-init.exe. It will start the installation in a console and present the above message on success.

For other installation options and information, visit the install page of the Rust website.

Uninstalling Rust is as easy as installing it:

$ rustup self uninstall

If weve got Rust installed, we can open up a shell, and type this:

$ rustc --version

You should see the version number, commit hash, and commit date.

If you do, Rust has been installed successfully! Congrats!

If you dont, that probably means that the PATH environment variable doesnt include Cargos binary directory, ~/.cargo/bin on Unix, or %USERPROFILE%\.cargo\bin on Windows. This is the directory where Rust development tools live, and most Rust developers keep it in their PATH environment variable, which makes it possible to run rustc on the command line. Due to differences in operating systems, command shells, and bugs in installation, you may need to restart your shell, log out of the system, or configure PATH manually as appropriate for your operating environment.

Rust does not do its own linking, and so youll need to have a linker installed. Doing so will depend on your specific system. For Linux-based systems, Rust will attempt to call cc for linking. On windows-msvc (Rust built on Windows with Microsoft Visual Studio), this depends on having Microsoft Visual C++ Build Tools installed. These do not need to be in %PATH% as rustc will find them automatically. In general, if you have your linker in a non-traditional location you can call rustc linker=/path/to/cc, where /path/to/cc should point to your linker path.

If you are still stuck, there are a number of places where we can get help. The easiest is .

This installer also installs a copy of the documentation locally, so we can read it offline. Its only a rustup doc away!

Now that you have Rust installed, well help you write your first Rust program. Its traditional when learning a new language to write a little program to print the text Hello, world! to the screen, and in this section, well follow that tradition.

The nice thing about starting with such a simple program is that you can quickly verify that your compiler is installed, and that its working properly. Printing information to the screen is also a pretty common thing to do, so practicing it early on is good.

Note: This book assumes basic familiarity with the command line. Rust itself makes no specific demands about your editing, tooling, or where your code lives, so if you prefer an IDE to the command line, thats an option. You may want to check out SolidOak, which was built specifically with Rust in mind. There are a number of extensions in development by the community, and the Rust team ships plugins for various editors. Configuring your editor or IDE is out of the scope of this tutorial, so check the documentation for your specific setup.

First, make a file to put your Rust code in. Rust doesnt care where your code lives, but for this book, I suggest making a projects directory in your home directory, and keeping all your projects there. Open a terminal and enter the following commands to make a directory for this particular project:

$ mkdir ~ /projects$ cd ~ /projects$ mkdir hello_world$ cd hello_world

Note: If youre on Windows and not using PowerShell, the ~ may not work. Consult the documentation for your shell for more details.

We need to create a source file for our Rust program. Rust files always end in a .rs extension. If you are using more than one word in your filename, use an underscore to separate them; for example, you would use my_program.rs rather than myprogram.rs.

Now, make a new file and call it