8.10. Scala cycle

Sometimes, we may need to execute the same piece of code multiple times. In general, statements are executed sequentially: the first statement in the function is executed first, then the second statement, and so on.

Programming languages provide a variety of control structures for more complex execution paths.

Loop statements allow us to execute a statement or group of statements multiple times. Here is a flowchart of loop statements in most programming languages:

8.10.1. Cycle type #

The Scala language provides the following loop types. Click the link to viewthe details of each type.

Cycle type

Description

While cycle

Run a series of statements that, if the condition is true, run repeatedly until the condition becomes false.

Do…while cycle

A similar while statement differs from a block of code that executes a loop before determining a loop condition.

for cycle

Used to repeat a series of statements until specific conditions are met, usually by increasing the value of the counter after each loop is completed.

8.10.2. Loop control statement #

Loop control statements change the order in which your code is executed, through which you can jump the code. Scala has the following loop control statements:

Scala does not support break or continue statement, but a way to break the loop has been provided since version 2.8. Click the link below fordetails.

Control statement

Description

Break statement

Break cycle

8.10.3. Infinite cycle #

If the condition is always the true loop becomes an infinite loop We can use it. while statement to implement an infinite loop:

Example #

object Test {
   def main(args: Array[String]) {
      var a = 10;
      // Infinite loop
      while( true ){
         println( "The value of a is : " + a );
      }
   }
}

The post-execution loop of the above code will be executed forever, and you can use the Ctrl + C key to break the infinite loop.

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