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Scala Option: A Gentle Introduction

Scala Option[ T ] is a compartment for nothing or one component of a given kind. An Option[T] can be either Some[T] or No object, which addresses a missing worth. For example, the get technique for Scala’s Map produces Some(value) if a value comparing to a given key has been or None if the given key isn’t mention in the Map.

Scala’s Option type is a fundamental concept in functional programming that addresses the challenge of representing absence of a value in a type-safe manner. Option is used to encapsulate an optional value that may or may not exist, providing a safer alternative to null references commonly used in other languages.

The Option type in Scala is defined as a generic container that can hold either a Some value, representing the presence of a value, or None, representing the absence of a value. This approach eliminates the risk of null pointer exceptions and encourages safer and more predictable code.

Use case 1:

object prwatech {
   // Main method
    def main(args: Array[String])
    {
  
        // Creating a Map
        val name = Map("Abhi" -> "author", 
                        "Prabha" -> "coder")
  
        // Accessing keys of the map
        val x = name.get("Abhi")
        val y = name.get("Sandeep")
  
        // Displays Some if the key is
        // found else None 
        println(x)
        println(y)
    }
}	

Output:

Some(author)
None

Here, key of the value Abhi  so, Some is return for it but key of the value Sandeep so, None is return for it.

Use case 2:

Using Pattern Matching:
object prwatech {
   // Main method
    def main(args: Array[String])
    {
  
        // Creating a Map
        val name = Map("Abhi" -> "author", 
                        "Prabha" -> "coder")
  
        //Accessing keys of the map
        println(patrn(name.get("Abhi")))
        println(patrn(name.get("Rahul")))
    }
  
    // Using Option with Pattern 
    // matching
    def patrn(z: Option[String]) = z match 
    {
  
        // for 'Some' class the key for
        // the given value is displayed
        case Some(s) => (s)
  
        // for 'None' class the below string 
        // is displayed
        case None => ("key not found")
    }
}

Output:

author
key not found

Use case 3:

getOrElse() Method:

This technique returns either a value in the event that is available or a default value when its not available. Here, For Some class a value is return and for None class a default value returns.Scala Option: A Gentle Introduction

object prwatech {
   // Main method
    def main(args: Array[String])
    {
  
        // Using Some class
        val some:Option[Int] = Some(5)
  
        // Using None class
        val none:Option[Int] = None 
  
        // Applying getOrElse method
        val x = some.getOrElse(0)
        val y = none.getOrElse(1)
  
        // Displays the key in the 
        // class Some
        println(x)
  
        // Displays default value 
        println(y)
    }
}

Output:

5
1