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Conditional statement in Rust

It’s similar with conditional statement from other programming language.
We can use if and else keyword. No need to wrap the condition inside rounded bracket ”(” and ”)“.

fn main() {
    let number = 3;

    if number < 5 {
        println!("condition was true");
    } else {
        println!("condition was false");
    }
}

Multiple condition with else if

fn main() {
    let number = 6;

    if number % 4 == 0 {
        println!("number is divisible by 4");
    } else if number % 3 == 0 {
        println!("number is divisible by 3");
    } else if number % 2 == 0 {
        println!("number is divisible by 2");
    } else {
        println!("number is not divisible by 4, 3, or 2");
    }
}

Non-boolean

Since, Rust is type sensitive, we’ll get an error if provide non-boolean as argument

fn main() {
    let number = 3;

    if number {
        println!("number was three");
    }
}

result

error[E0308]: mismatched types

Variable declaration based on condition

We can do ternary operator in Rust like this:

fn main() {
    let condition = true;
    let number = if condition { 5 } else { 6 };

    println!("The value of number is: {}", number);
}

The value in left side and right side (5 and 6 in the above case) must have same data type.

rust