How to Reassignment to a Val in Scala

1. Reassignment to a val in Scala
2. Conclusion

This article will teach about reassignment to a val in Scala.

Reassignment to a val in Scala

In Scala, reassignment to val is not allowed, but we can create a new val and assign the value to it.

Example code 1:

object MyClass {

    def main(args: Array[String])
    {
         val x = 10;
         x = x+10

         println(x)
    }
}

Output:

error: reassignment to val

We can see an error when reassigning the values to a val.

As a workaround, we can assign the result to a new val and use it.

Example code 2:

object MyClass {

    def main(args: Array[String])
    {
         val x = 10;
         val y = x+10

         println(y)
    }
}

Output:

20

Scala provides us with three ways to define things.

1. val is used to define a fixed value, which cannot be modified.

   Example code: Here, the val x cannot be modified.

   object MyClass {
   
   	def main(args: Array[String])
   	{
   		 val x = 10;
   
   	}
   }
   

2. var is used to define a variable, a value that can be modified.

   object MyClass {
   
   	def main(args: Array[String])
   	{
   		 var x = 10;
   		 x = x+10;
   		 println(x)
   
   		 x = x*1000
   		 println(x)
   
   	}
   }
   

   Output:

   20
   20000
   

3. def is used to define a method

   Example code:

   object MyClass {
   
     def student = 2*3*4*5*6
   
   	def main(args: Array[String])
   	{
   		 println(student)
   	}
   }
   

   Output:

   720
   

Conclusion

In this article, we learned that we could not reassign values to a val as it declares the variable as the fixed value, so if we want to use a variable that keeps changing constantly, we can use var.