Mention the types of Variables in Scala? And What is the difference between them?

Category : Scala | Sub Category : Scala Interview Questions | By Prasad Bonam Last updated: 2023-09-27 00:26:45 Viewed : 273

Mention the types of Variables in Scala? And What is the difference between them?

In Scala, variables can be categorized into two main types: mutable and immutable. These types of variables have different characteristics and use cases:

1. Mutable Variables:

   • var: Mutable variables are declared using the var keyword. Once assigned a value, you can change the value of a var variable during its lifetime.
   • Example:

     scalaCopy code
     var mutableVariable: Int = 10
     mutableVariable = 20 // Valid, the value can be changed
     

2. Immutable Variables:

   • val: Immutable variables are declared using the val keyword. Once assigned a value, you cannot change the value of a val variable. They are essentially constants.
   • Example:

     scalaCopy code
     val immutableVariable: String = "Hello"
     // Attempting to change the value will result in a compilation error:
     // immutableVariable = "World" // Error: Reassignmen
     

The key difference between var and val in Scala is that var allows for variable reassignment, while val does not. Immutable variables (val) are preferred in functional programming and concurrent programming because they are inherently thread-safe and can help prevent unintended changes to data. They also promote a more functional programming style, which can lead to more predictable and maintainable code.

Here is a summary of the differences:

• var is mutable, while val is immutable.
• Mutable variables (var) can have their values reassigned, while immutable variables (val) cannot be reassigned after initialization.
• Immutable variables (val) are thread-safe, which can be beneficial in concurrent programming.
• Using val encourages a functional programming style and can lead to more predictable and maintainable code.