praveenlearning

'''
SingleTon class definition

_instance reference of single instance of the class
'''
class SingleTon:
    '''
    reference to the single instace
    '''
    _instance = None

praveenlearning

@main
def main(): Unit =
    println(2.square)
    // Prints 4 in this example
   
extension (value: Int)
    def square: Int = value * value

praveenlearning

object Runner extends App {

  // To be imported for implicit context
  import Implicits.IntPlus

  println(2.square)
  // Prints 4 in this example
}

object Implicits {

praveenlearning

import scala.util.CommandLineParser.FromString

given FromString[List[Int]] with
	def fromString(s: String): List[Int] = s.split(" ").map(_.toInt).toList

// ex: cmd args = "1 2 3 4 5 6 7 8 9"
@main
def main(numbers: List[Int]): Unit =
	println(numbers)
	// prints => List(1, 2, 3, 4, 5, 6, 7, 8, 9)

praveenlearning

// unary methods such as +, -, !, ~ can be achived with defining methods with unary_ as prefix

class Person(name: String):
  // definition of unary function
  def unary_! : Person =
    Person(name.reverse)

  override def toString: String = s"Person($name)"

praveenlearning

// any method ends with : (colon) will have right assossiative.
// this is only applicable to methods having single argument.

// using scala 3

class Person:
  def >>:(any: String) =
    println(any)