Rust Function: Print optional integer

Last update on December 21 2024 10:18:32 (UTC/GMT +8 hours)

Write a Rust function that takes an optional integer and prints its value if it exists.

Sample Solution:

Rust Code:

// Define a function named 'print_optional_integer' that takes an optional integer 'num' as input
fn print_optional_integer(num: Option) {
    // Match on the 'num' parameter to handle both Some and None cases
    match num {
        // If 'num' contains a value, print it
        Some(value) => println!("The value is: {}", value),
        // If 'num' is None, print a message indicating absence of value
        None => println!("The value is absent"),
    }
}

fn main() {
    // Call the 'print_optional_integer' function with Some and None values
    print_optional_integer(Some(42)); // Prints: The value is: 42
    print_optional_integer(None);     // Prints: The value is absent
}

Output:

The value is: 42
The value is absent

Explanation:

Here's a brief explanation of the above Rust code:

• fn print_optional_integer(num: Option<i32>) { ... }: This function is defined to take an Option<i32> as input, representing an optional integer.
• match num { ... }: This is a match expression that matches on the 'num' parameter to handle both 'Some' and 'None' cases.
• Some(value) => println!("The value is: {}", value),: This arm of the match expression is executed if 'num' contains a value ('Some'). It extracts the value from 'Some' and prints it.
• None => println!("The value is absent"),: This arm is executed if 'num' is 'None'. It prints a message indicating the absence of a value.
• fn main() { ... }: This is the entry point of the program. It calls the "print_optional_integer()" function with both 'Some' and 'None' values to demonstrate its functionality.

Rust Code Editor:

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