📌 Rust String Concatenation: Ownership & Borrowing

📖 Task Details

In this task, students will create a simple Rust program that demonstrates the concepts of ownership, borrowing, and references. The program will take two strings as input, concatenate them, and then print the result without violating any ownership rules.

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🚀 Program Code

fn concatenate_strings(str1: &str, str2: &str) -> String {
    let mut result = String::new(); // mutable variable
    result.push_str(str1);
    result.push_str(str2);
    return result;
}

fn main() {
    let string1: String = String::from("hello");
    let string2: String = String::from(" world");
    let concatenated_string = concatenate_strings(&string1, &string2); // & for borrowing 
    println!("{}", concatenated_string);
}

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📝 Explanation

• The function concatenate_strings takes two borrowed string slices (&str).
• This prevents ownership transfer, allowing string1 and string2 to still be used after the function call.
• A new String is created inside the function, modified with push_str(), and returned.
• In main(), the function is called using borrowed references (&string1 and &string2).
• This ensures no ownership violations while efficiently concatenating the strings.

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✅ Expected Output

hello world

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📌 Key Concepts Demonstrated

• Ownership: The function does not take ownership of string1 and string2, allowing them to be reused.
• Borrowing & References: The function parameters use &str, enabling safe and efficient string handling.
• String Manipulation: Using push_str() to append borrowed string slices to a mutable String.

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🔥 Running the Program

1️⃣ Ensure you have Rust installed:

rustc --version

If Rust is not installed, install it using:

curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh

2️⃣ Compile and Run the Program:

rustc main.rs
./main

OR using Cargo:

cargo run

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