Rust

Install rust or, if already installed but outdated, update with rustup update.

Compile with rustc main.rs.

Cargo handles crates. A crate can be binary or library crate.

Create a new project with cargo new.

Build project with cargo build and then run the project with ./target/debug/[project_name]. If you want to create a optimized version of the build then do cargo build --release.

Run project with cargo run.

Check a project for errors with cargo check.

The cargo lock file stores the complete dependency tree for the build. It is a good idea to keep that under version control. To update the dependency tree, first update the dependencies section in the Cargo.toml file and then run cargo update.

Result is an enumeration, also called as enum. An enum is a type which can be in one of multiple possible states. One of the possible states is called a variant.

The result variants are Ok and Err. The Ok variant indicates the operation was successful, and inside Ok is the successfully generated value. The Err variant means the operation failed, and Err contains information about how or why the operation failed. If this instance of Result is an Err value, expect will cause the program to crash and display the message that you passed as an argument to expect. If the read_line method returns an Err, it would likely be the result of an error coming from the underlying operating system. If this instance of Result is an Ok value, expect will take the return value that Ok is holding and return just that value to you so you can use it. In this case, that value is the number of bytes in the user’s input.

You can handle errors with a "match" statement.

let guess: u32 = match guess.trim().parse() {
   Ok(num) => num,
   Err(_) => continue, // underscorde (_) is a catchall value.
}

The syntax ::[function_name] indicates that "function_name" is an associated function. For example let mut variable = String::new();, is creating a mutable variable of type String with the function "new".

The loop keyword creates an infinite loop.

The match expression is made up of arms. An arm consits for a pattern to match against and the code that should be run if the value given to match fits the arm's pattern.