Understanding String and &str Types

Snippet

Understanding String and &str Types

Rust has two main string types: String (owned, heap-allocated, growable) and &str (borrowed string slice pointing to existing data). Understanding this distinction is crucial for memory management and performance in Rust applications.

snippet.rs
rust
fn main() {
    let owned: String = String::from("Hello");
    let borrowed: &str = "World";
    let combined: String = owned + ", " + borrowed;
    let slice: &str = &combined[0..5];
    println!("Combined: {}", combined);
    println!("Slice: {}", slice);
}

Breakdown

String::from("Hello")

Creates an owned String allocated on the heap

let borrowed: &str = "World";

Creates a string slice reference pointing to static memory

owned + ", " + borrowed

Concatenates strings using the + operator (borrowed is coerced)

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Understanding String and &str Types

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