Scala Do-While Loop

The do-while loop in Scala is a control structure that executes a block of code repeatedly based on a specified condition. Unlike the while loop, the do-while loop guarantees that the code block will run at least once before the condition is evaluated.

Key Concepts

• Syntax: The basic structure of a do-while loop is:

do {
    // Code to execute
} while (condition)

• Execution Flow:
  • The code inside the do block is executed first.
  • After executing the block, the condition is checked.
  • If the condition is true, the loop continues; if false, the loop ends.

Characteristics

• At Least One Execution: The loop ensures that the code block runs at least once, regardless of the condition.
• Condition Evaluation: The condition is evaluated after the execution of the code block.

Example

Here’s a simple example of a do-while loop in Scala:

var number = 1

do {
    println(s"Number: $number")
    number += 1
} while (number <= 5)

Explanation of the Example:

• Initialization: A variable number is initialized to 1.
• Loop Execution:
  • The loop prints the current value of number.
  • number is then incremented by 1.
• Condition: The loop continues until number is greater than 5.

Output of the Example:

Number: 1
Number: 2
Number: 3
Number: 4
Number: 5

Conclusion

The do-while loop is a valuable construct in Scala for scenarios where at least one execution of the loop body is required. It provides a straightforward way to repeat actions based on conditions, making it a fundamental concept in programming with Scala.