Writing a condition

Similar to other languages, Rust conditions are expressed with the if and else keywords:

let number1 = 24;
let number2 = 42;
if number1 > number2 {
    println!("{} > {}", number1, number2);
} else {
    println!("{} <= {}", number1, number2);
}

However, they do not require parentheses around the conditional expression. Also, this expression must be of the bool type: you cannot use a number as you would in other languages.

One particularity of Rust conditions, like many other constructs, is that they are expressions. The last expression of each branch is the value of this branch. Be careful though, the type of each branch must be the same. For instance, we can get the minimum number of the two numbers and put it into a variable:

let minimum =
    if number1 < number2 {
        number1
    } else {
        number2
    }; // Don't forget the semi-colon here.