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Advanced 16 min readModule: Module 6: Structs & Methods

Structs, Impl Blocks & Associated Functions

Define custom domain records with structs and attach methods and constructors via 'impl' blocks.

What You Will Learn in This Lesson

  • Defining named-field structs and tuple structs
  • Method receivers: &self (borrow), &mut self (mutate), self (consume)
  • Associated constructor functions (Self::new)

Introduction & Core Concept

Structs are custom data types that let you package together and name multiple related values into a meaningful group.
WHY DOES THIS MATTER IN THE REAL WORLD?

Attaching methods via 'impl' blocks cleanly separates data definition from behavioral algorithms.

Rectangle Struct with Method Implementation

rust
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#[derive(Debug)]
struct Rectangle {
    width: u32,
    height: u32,
}
 
impl Rectangle {
    fn new(w: u32, h: u32) -> Self {
        Self { width: w, height: h }
    }
    fn area(&self) -> u32 {
        self.width * self.height
    }
}
 
fn main() {
    let rect = Rectangle::new(30, 50);
    println!("Rect: {:?} | Area: {}", rect, rect.area());
}

Line-by-Line Technical Breakdown

1Associated functions without &self act like static factory methods in other languages.

Try It Yourself (Interactive Editor)

Modify the code in real-time and click Run to test live browser output and console logs.

Intelligent Code Runner & Live Sandbox[RUST]
RUST SOURCE EDITOR
Interactive Live Code

Industry Best Practices & Professional Standards

  • Always provide a new() associated constructor function for complex structs.

Lesson Summary & Core Takeaways

  • Structs and impl blocks structure data and behavior cleanly.