Scala Collections - DropWhile Method

dropWhile() method is method used by List to drop all elements which satisfies a given condition.

Syntax

The following is the syntax of dropWhile method.

def dropWhile(p: (A) => Boolean): List[A]

Here, p: (A) => Boolean is a predicate or condition to be applied on each element of the list. This method returns the all the elements of list except dropped ones.

Usage

Below is an example program of showing how to use dropWhile method −

Example

object Demo {
   def main(args: Array[String]) = {
      val list = List(3, 6, 9, 4, 2)
      // print list
      println(list)
      //apply operation
      val result = list.dropWhile(x=>{x % 3 == 0})
      //print result
      println(result)      
   }
}

Save the above program in Demo.scala. The following commands are used to compile and execute this program.

Command

\>scalac Demo.scala
\>scala Demo

Output

List(3, 6, 9, 4, 2)
List(4, 2)