Rust Loops Tutorial | loop while for for Beginners (2024)

Rust Loops Tutorial: loop, while, and for Explained

This tutorial covers the three primary loop types in Rust: the infinite loop with break, the conditional while loop, and the range-based for loop. You'll learn how to use each loop effectively with clear examples and explanations.

Code

fn main() {
  // Example 1: Infinite loop with break
  let mut count = 0;
  loop {
    count = count + 1;               // Increment count
    println!("Count is: {}", count);
    if count == 5 {
      break;                        // Exit loop when count reaches 5
    }
  }

  // Example 2: While loop countdown
  let mut seconds = 5;
  while seconds > 0 {             // Continue while seconds is greater than 0
    println!("{} seconds remaining...", seconds);
    seconds = seconds - 1;          // Decrement seconds
  }
  println!("Liftoff!");

  // Example 3: For loop with range
  for number in 1..6 {              // Range 1 to 5 (6 is excluded)
    println!("Number: {}", number);
  }
  // Use 1..=5 for an inclusive range that includes 5
}

Key Points

• loop creates an infinite loop that must be exited with break.
• while loops continue as long as a condition remains true.
• for loops iterate cleanly over ranges or collections.
• Ranges like 1..6 exclude the end value, while 1..=5 includes it.
• Declare variables as mut when you need to modify them inside loops.