What is Cargo in Rust

Cargo is Rust’s build system and package manager. It’s an optional tool, but it handles a lot of tasks to work with Rust.

Tasks include:

build your project with cargo build
run your project with cargo run
test your project with cargo test
build documentation for your project with cargo doc
publish a library to crates.io with cargo publish

We may not need this for now (at least for learning syntax or hello world program). But soon when we need a package or our program stars growing. It will comes in handy!

Hello World with Cargo

We’ve build hello world before. Now let’s build it with helps from Cargo.

cargo new hello_cargo

It create a new project and binary (application) hello_cargo. You can chanel hello_cargo with your own project name.

cd hello_cargo

Take a look inside this dir. It creates:

A src folder for our source code with hello world example
A .gitignore file.
and a configuration file called 'cargo.toml'

Build a Rust program with Cargo

Now we can build and run our hello world program with Cargo

cargo build

Just like before, it will create an executable file for us to run. Now try

./target/debug/hello_cargo

For Windows

.\target\debug\hello_cargo.exe

Cargon run for short

To do both of the job in one command, try

cargo run

It compiles the code and then run the resulting executable. It’s our hello world program

Check your program

If you don’t need to compile (the executable file) just yet. You can always run

cargo check

just to check our code.

Building for release

If you are ready to fly on production, we can use

cargo build --release