Ownership

Ownership

It's a unique & critical aspect of Rust.

In C/C++ there is no concept called a Garbage Collector. (which frees up the unused memory).

• But they are very fast and performant.
• Developers need to work to free up memory. (remember free() function?)

In other languages such as Python, Java, and Go we have Garbage Collector

• Relatively slower
• Developers can focus only on business logic.

Rust Ownership System

• Best of both worlds.
• The Compiler replaces most of GC's responsibilities.
• Determines at compile time when memory is allocated and deallocated.
• Requires developers to code in specific ways. (All the checks and balances)

Rules of Ownership

• Each value in Rust has a variable that is called its Owner.
• There can only be one owner at a time.
• When the owner goes out of scope, the value will be dropped.

{:p} - Pointer Trait, used to print the memory location of variables.

// Demonstrate Shadowing

fn main() {
    let x = String::from("Rachel");
    println!("Memory address of x: {:p}", &x);
    
    // new x is created in another memory location
    let x = 5;
    println!("Memory address of x: {:p}", &x);
}