RUST learning note

1. Installation

curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh

Set default channel, ex. “stable”: rustup default stable
Update: rustup update
Uninstall Rust: rustup self uninstall

2. Data type

Data type should be defined when it’s build, unlike script languages.

  • Integer: u8 -> i128
  • Float: f32, f64
  • Bool: true, false. 0 cannot be taken as false.
  • Char: ‘a’
  • Tuple: (int, bool, char, float)
  • Array: (int, int, …), (float, float, …)
  • Vector: Similar to Array, but length is changable
  • HashMap(key, val): for storage
  • BTreeMap(key, val): can compare elements, less efficient when insert item
  • HashSet(val)
  • BTreeSet(val)
  • Enum: (val(Type)), can assign defferent types for values

    3. Logic control

  • if, else if
  • match 
    match a {
  0 => println!("zero")
  1..=i32::MAX => println!("positive")
  _ => println!("negative")
}
  • loop: need “break;” to get out
  • while
  • for: ex. for num in 1..5, 5 is not iterated

    4. Exception

  • Option: check null pointer
  • Result: check return value of process
  • panic 
    use std::panic
panic!("Un-solvable error")

    5. Cargo

    Cargo is a package management tool. Useful commands:

    Cargo new $PROJECT_NAME <--lib>
Cargo build <--release>
Cargo run
Cargo check     # check dependencies
Cargo test      # unit test
  • Cargo.toml Toml file defines build content, like a cmake file ```toml [package] name = “example” version = “0.1.0” authors = [“someone someone@someorg.com”] edition = “2022”

[[bin]] name = “example_bin” path = “src/main.rs”

[dependencies] … ```