2. Learning Scala - Basics.scala

// Databricks notebook source
val f = (x:Int) => x + 1

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f(7)

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val g = () => 100

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g()

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//Methods
def add(x:Int,y:Int): Int = x + y
add(13,24)

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class FullName( firstname:String, lastname:String){
  def name(): String = firstname + lastname
}

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val fullname = new FullName("Awantik","Das")

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fullname.name()

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case class Point(x:Int, y:Int)

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//You can instanciate case classes without new keyword
//case classes are immutable
//Compared by value
val point = Point(1,2)
val anotherPoint = Point(1,2)


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point == anotherPoint

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val new_fullname = new FullName("Awantik","Das")

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//Since normal classes are compared by address
fullname == new_fullname

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//Objects
//They are single instances of their own defination
//Singleton of their own classes
//Define obect using object keyword

object Factory{
  private var ctr = 0
  def construct(): Int = {
    ctr += 1
    ctr // No need to write return, automatically return ctr
  }
}


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val newCtr = Factory.construct()
println(newCtr)

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val newCtr2 = Factory.construct()
println(newCtr2)

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//Traits are types containing certain fields & methods
trait GreatWall{
  def great(name:String): Unit
}

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trait DefaultGreatWall{
  def great(name:String): Unit =
     println("This is default print")
}

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class MyGreatWall extends DefaultGreatWall

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class NewGreatWall extends GreatWall{
  def great(name:String): Unit =
     println("This is NewGreatWall print")
}

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val ngw = new NewGreatWall()

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ngw.great("6 feet")

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