Resources

Update Rust with Rustup

$ rustup update

Compile and run apps with Rustc

Compile:

$ rustc file.rs

Execute the binary output file:

$ # On Unix.
$ ./file

> # On Windows.
> file.exe

Or compile and run - in one line:

$ # On Unix.
$ rustc file.rs && ./file

Formatting

Automatic code formatter.

$ cargo fmt

Linting

Linting to catch common API misuses and unidiomatic code.

$ cargo clippy

Manifest commands

Note that Rust packages are not stored in your project itself, but in a global cache directory.

Tree

Check the dependency graph.

$ cargo tree

Install project packages

Here, I’ve manually added the rand crate, which is currently on top the most-downloaded Crates list.

[dependencies]
rand = "0.8.0"

If you don’t know the version, just leave as "". You’ll see the version logged next.

To download and install packages on your dependencies list, run one of:

$ cargo build
$ cargo run

Update

doc

cargo-update - Update dependencies as recorded in the local lock file

This will install any missing crates listed in Cargo.toml dependencies and will also upgrade packages and save changes in the lockfile.

$ cargo update

For example, using:

[dependencies]
rand = "0.8.0"

This crate and its dependencies will get added to the lockfile. But they will not be installed until your run build or run.

$ cargo update

    Updating crates.io index
      Adding cfg-if v1.0.0
      Adding getrandom v0.2.2
      Adding libc v0.2.84
      Adding ppv-lite86 v0.2.10
      Adding rand v0.8.3
      Adding rand_chacha v0.3.0
      Adding rand_core v0.6.1
      Adding rand_hc v0.3.0
      Adding wasi v0.10.2+wasi-snapshot-preview1

Additionally, if you remove a package from your Cargo.toml list of dependencies, then running cargo update will also remove unneeded packages in your Cargo.lock file.

Run

$ cargo run
$ cargo r
$ cargo run src/main.rs

That will create the target directory and add intermediate files to it.

This step will also download and install any missing packages.

Building

Check

This is faster than doing build command.

$ cargo check

It will install dependencies If you removed a package from Cargo.toml, this comamnd will also remove the unnecessary dependencies from the lockfile.

Build package

  • cargo build

    Compile the current package

This will download and install any missing packages and compile your app to an output directory - target by default.

$ cargo build

Run the output binary in a debug directory.

target/debug/rust-project-template
Hello, World!

Do a production-optimized build.

$ cargo build --release

Run the output binary in a release directory.

target/release/rust-project-template
Hello, World!

Cargo is a package manager, not a compiler. It runs the Rustc compiler for you (with a lot of options) and does some extra work (e.g. resolves dependencies and check if the compile step should run).

  • --target TARGET - Directory for all generated artifacts and intermediate files. Defaults to target directory. Can be overridden as a flag or env variable or config option.
  • --out-dir OUT - Copy final artifacts to this directory. Unstable and only on nightly channel.

Compile

Output a binary using rustrc compiler. This useful if you have a Rust project which is not structured for distribution as a Cargo pacakge.

The cargo build command will run the rustc compiler internally.

Compile the main script - this will output as main in the project root.

$ rustc src/main.rs

Run the output binary:

$ ./main
Hello, World!

Output to custom path.

$ rustc src/main.rs -o build/rust-project-template

$ build/rust-project-template
Hello, World!

Docs

Generate HTML docs from your code.

$ cargo doc

Check the contents:

$ ls target/doc

COPYRIGHT.txt
...
rust-logo.png
rust_project_template/
...
src/
...
wheel.svg

Notable HTML paths in doc:

  • rust_project_template/index.html
  • rust_project_template/main.rs.html

Build docs and open the browser automatically.

$ cargo doc --open

The full path to the index.html on disk is used.

e.g. /Users/mcurrin/repos/rust-project-template/target/doc/rust_project_template/index.html

Relative paths are used for assets - e.g. href="../normalize.css".

This doc sites does’t seem to need a web server to run. In fact, if you start a web server in doc/rust_project_template, you’ll be unable to load assets on level up. So you will have to start a web server in doc where there is no index.html file, then navgiate to /rust_project_template/.