HPR3453: Rust 101: Episode 1 - Hello, World!

Talking Points

• main.rs
  • Like main.cpp in C++ or main.c in C
  • Tells the compiler which file to start with
  • Can link to other "crates" and "modules"
• Cargo.toml
  • Keeps track of application metadata
  • This includes dependencies!
• Functions
  • Strictly typed, like everything in Rust
  • Declared by fn
  • Argument typed with argument: Type
  • Return typed with -> Type otherwise assumed to return nothing
• The Main Function
  • Like the main functions in C and C++
  • Where the program starts within the main.rs file
  • CLI arguments handled by std::env, rather than argv and argc in C
  • Can return nothing or a Result<()>
• Macros
  • Metafunctions or functions for functions
  • More general than functions, having flexibility in the number of arguments, etc, but harder to write
• The println! Macro
  • Can take any number of arguments that implement the display trait
  • Usually things like strings or character literals
  • Will format them into a string and display it on the terminal
  • Similar to printf in C
• The Hello World program
  • Can be automagically generated with cargo new and then the name of your application
  • Located in Name-Of-Application/src/main.rs

fn main() {
  println!("Hello, world!");
}

Show Notes

Important Links:

• Git repo for this miniseries
• The Rust Standard Library
• The format! macro
• The println! macro

Wikipedia Articles:

• The Rust Programming Language

• Email: izzyleibowitz at pm dot me
• Mastodon: at blackernel at nixnet dot social

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