Apply Closure to concatenated strings in Rust

Rust Closures and Higher-Order Functions: Exercise-9 with Solution

Write a Rust function that takes a closure and two strings, concatenates the strings, and applies the closure to the concatenated string.

Sample Solution:

Rust Code:

fn apply_closure_to_strings<F>(str1: &str, str2: &str, closure: F) -> String
where
    F: FnOnce(String) -> String, // Closure trait bound
{
    let concatenated_string = format!("{}{}", str1, str2); // Concatenate the strings
    closure(concatenated_string) // Apply the closure to the concatenated string and return the result
}

fn main() {
    let str1 = "Rust, ";
    let str2 = "Exercises!";
    let result = apply_closure_to_strings(str1, str2, |s| s.to_lowercase()); // Example usage: converting the concatenated string to lowercase
    println!("{}", result); // Print the result
}

Output:

rust, exercises!

Explanation:

In the exercise above,

• apply_closure_to_strings: This function takes two string slices 'str1' and 'str2', and a closure 'closure' as arguments. The closure takes a "String" and returns a "String".
• Inside the function, the 'str1' and 'str2' are concatenated using the format! macro to create 'concatenated_string'.
• The closure 'closure' is then applied to the concatenated string, and the result is returned.
• In the "main()" function, an example usage of "apply_closure_to_strings()" is demonstrated. It concatenates two strings "Rust, " and "Exercises!", and applies a closure that converts the concatenated string to lowercase.
• Finally, it prints the result.

Rust Code Editor:

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