Type Casting

Part of the Fundamentals section of Coddy's Rust journey — lesson 14 of 75.

Type casting is the process of converting a value from one data type to another. In Rust, we use the as keyword for explicit type casting (also known as type conversion).

The most common type conversions are between numeric types:

// Integer to Float conversion
let number: i32 = 5;
let decimal: f64 = number as f64;
// becomes 5.0

// Float to Integer conversion
let decimal: f64 = 9.7;
let number: i32 = decimal as i32;
// becomes 9 (decimal part is truncated)

Challenge

Beginner

Write a Rust program that demonstrates type casting. Perform the following operations:

Declare an f64 variable named price and initialize it with the value 99.99.
Cast the price variable to an i32 and store the result in a new variable named int_price.
Print the values of price and int_price, to the console.

Cheat sheet

Type casting converts a value from one data type to another using the as keyword:

// Integer to Float conversion
let number: i32 = 5;
let decimal: f64 = number as f64;
// becomes 5.0

// Float to Integer conversion
let decimal: f64 = 9.7;
let number: i32 = decimal as i32;
// becomes 9 (decimal part is truncated)

Try it yourself

fn main() {
    // Declare and initialize variables
    let price: f64 = 99.99;
    let int_price: i32 = ?;
    
    
    // Output the values
    println!("Price: {}", price);
    println!("Int Price: {}", int_price);
    
}