Rust While Loops

The while Loop

The while loop runs as long as a condition is true.

Example

  let mut count = 1;

  while count <= 5 {

  println!("Count: {}", count);

  count += 1;

  }

In the example above, the loop keeps running as long as the counter is less than or equal to 5.

It prints the numbers from 1 to 5, one on each line.

False Condition

The while loop checks the condition before each loop, so if the condition is false at the start, the loop will not run at all:

Example

    let count = 10;

    while count <= 5 {

  println!("This won't be printed.");

    }

Stop a While Loop

You can stop a while loop when you want by using break:

Example

  let mut num = 1;

  while num <= 10 {

  if num == 6 {

    break;

  }

  println!("Number: {}", num);

  num += 1;

  }

This prints numbers from 1 to 5 (stops the loop when num reaches 6).

Next: Learn how to use the for loop to go through a range of values.

Skip a Value

You can skip a value by using the continue statement:

Example

  let mut num = 1;

while num <= 10 {
  if num == 6 {
    num += 1;

      continue;
  }

   
  println!("Number: {}", num);
  num += 1;
}

This prints numbers from 1 to 10, except for the number 6.

Next: Learn how to use the for loop to go through a range of values.