Rust Distilled

The else if statement allows you to specify a new condition to check if the previous if condition is false. This helps in checking multiple conditions sequentially.

• Syntax

#![allow(unused)]
fn main() {
if condition1 {
    // code to execute if condition1 is true
} else if condition2 {
    // code to execute if condition2 is true
} else {
    // code to execute if none of the above conditions are true
}
}

Example

Here is a simple example on how to use the else-if branch to check another condition:

fn main() {
    let number = 0;

    if number > 0 {
        println!("The number is positive.");
    } else if number < 0 {
        println!("The number is negative.");
    } else {
        println!("The number is zero.");
    }
}
main();

The number is zero.

Code in details: In the previous example: - The first condition number > 0 is false. - The second condition number < 0 is also false. - Since both conditions are false, the code inside the else block is executed, printing "The number is zero."

Using Conditions with let Bindings

Rust allows you to use if, else, and else if conditions in combination with let bindings for more concise and expressive code. This section will be explained in more details in the next section.

Here is the general syntax of this concept in Rust:

#![allow(unused)]
fn main() {
let my_var = if cond {result} else {the_other_result} 
}

Example

fn main() {
    let number = 5;
    let is_positive = if number > 0 {
        true
    } else {
        false
    };

    println!("Is the number positive? {}", is_positive);
}
main();

Is the number positive? true

The variable is_positive is assigned the value true if number > 0 and falseotherwise. This is a concise way to handle simple conditions and bindings.

we can extend the previous example to check for multiple conditions where needed by introducing an else-if branch. This is will be discussed in the next section.

Example Combining All Concepts

This is a comprehensive example that shows how to use conditionals in Rust:

fn main() {
    let number = 10;

    let description = if number > 0 {
        "positive"
    } else if number < 0 {
        "negative"
    } else {
        "zero"
    };

    println!("The number is {} and it is {}.", number, description);
}
main();

The number is 10 and it is positive.

In this comprehensive example, the description variable is assigned a string based on the value of number, and the final message prints out the number and its description. This demonstrates the flexibility and power of Rust's control flow structures.

Summary

• else if Statement: Allows for checking multiple conditions sequentially.
• Using Conditions with let Bindings: Enables concise and expressive code by combining conditions with variable bindings.