2)Scala Declare Variables And Types

Scala Declare Variables And Types
Variables are the placeholders for values in scala

There are two types of variables:

1. Immutable variables
2. Mutable variables

1)Immutable variables:(non-changable)

To define immutable variable, we use the keyword val

Syntax:

val <Name of varibale>: <Scala_type> = <Value literal>

Example:

var number: Int = 5

Note:
If you try to make any changes to the Immutable varibale, scala will return an exception, says, reassignment not allow for val.

2)Mutable variables:
To declare a variable as mutable, we use the keyword var

Syntax:

var <Name of variable> : <Scala_type>

Example:

Scala Types:

Following below are the scala types:

Note:

1. Any is the supertype of all types, also called the top type.
2. Any has two direct subclasses: AnyVal and AnyRef.

Example:

Other concepts related to varibles:
Lazy initialization:
Using Lazy initialization to delay the initialization of some variable until at the some point.
This can be done using lazy keyword

Syntax:

lazy val <Name of variable> = "literal value" 

Note:

• In the above we doesn't specify the type of string, 
• The Scala compiler knew that it should be of type String. This is called type inference 

Declare a variable with no initialization:
Use the wildcard operator _ when defining our variable.

Example:

var number: Int = _
number = 10