How to use the command cargo (with examples)

Cargo is a command-line tool for managing Rust projects and their dependencies. It provides several subcommands that perform different tasks related to Rust projects. This article will illustrate different use cases of the cargo command with examples.

Use case 1: Search for crates

Code:

cargo search search_string

Motivation: The cargo search command allows users to search for crates (Rust libraries) available on the official crates.io registry. This helps developers find and discover existing libraries that they can use in their Rust projects.

Explanation:

• search_string is the text to be searched. It can be a crate name or any keyword related to the desired crate.

Example output:

criterion (0.3.0) - Statistical tracking and benchmarking
libc (0.2.88) - A low-level library to use libc functionality in Rust

Use case 2: Install a binary crate

Code:

cargo install crate_name

Motivation: The cargo install command is used to install binary crates. Installing a binary crate makes the corresponding executable available for use on the system.

Explanation:

• crate_name is the name of the crate to be installed.

Example output:

    Updating crates.io index
  Installing diesel_cli v1.4.4  Running `...`
   Compiling ...
    ...
   Installing ...

Use case 3: List installed binary crates

Code:

cargo install --list

Motivation: The cargo install --list command provides a list of all binary crates that have been installed using cargo install. This is useful for managing installed crates and verifying their presence on the system.

Explanation: The --list flag is used to signal that we want to list the installed binary crates.

Example output:

diesel_cli v1.4.4
sqlx-cli v0.5.7

Use case 4: Create a new binary or library Rust project

Code:

cargo init --bin|lib path/to/directory

Motivation: The cargo init command is used to create a new Rust project. This command generates the required files and directories to start a new project, saving developers from the hassle of setting things up manually.

Explanation:

• --bin|lib specifies whether the project should be a binary or library project.
• path/to/directory specifies the directory in which the project should be created. If not provided, the command will use the current working directory.

Example output:

     Created binary (application) `my_app` package

Use case 5: Add a dependency to Cargo.toml

Code:

cargo add dependency

Motivation: The cargo add command allows users to easily add a dependency to their Rust projects. This command updates the Cargo.toml file and automatically fetches and includes the specified dependency in the project.

Explanation:

• dependency is the name of the crate to be added as a dependency.

Example output:

    Updating crates.io index
  Adding reqwest v0.11.4 to dependencies in Cargo.toml

Use case 6: Build the Rust project using the release profile

Code:

cargo build --release

Motivation: The cargo build command compiles a Rust project and produces the corresponding binary. Building with the --release flag enables optimizations for performance, producing a more optimized and faster binary.

Explanation:

• --release flag instructs the build process to use the release profile.

Example output:

    Compiling my_app v0.1.0 (/path/to/my_app)
    Finished release [optimized] target(s) in 3.41s

Use case 7: Build the Rust project using the nightly compiler

Code:

cargo +nightly build

Motivation: The cargo +nightly build command is used to build a Rust project using the nightly version of the Rust compiler. This allows developers to use features and enhancements that are not yet available in the stable Rust release.

Explanation:

• +nightly specifies that the nightly version of the Rust compiler should be used for building the project.

Example output:

    Compiling my_app v0.1.0 (/path/to/my_app)
    Finished dev [unoptimized + debuginfo] target(s) in 2.88s

Use case 8: Build using a specific number of threads

Code:

cargo build --jobs number_of_threads

Motivation: The cargo build command utilizes multiple threads by default to speed up the build process. However, there may be cases where the number of threads can be customized to optimize resource usage or manage build times.

Explanation:

• --jobs number_of_threads allows users to specify the number of threads to be used for building the project.

Example output:

    Compiling my_app v0.1.0 (/path/to/my_app)
    Finished dev [unoptimized + debuginfo] target(s) in 5.88s

Conclusion:

The cargo command is an essential tool for managing Rust projects. It provides convenient features for searching crates, installing binary crates, creating new projects, adding dependencies, and building projects with various configurations. Utilizing these features can greatly enhance the development experience with Rust.