scala for the impatient excercise 6

// 1. Write an object Conversions with methods inchesToCentimeters, gallonsToLiters, and milesToKilometers.

object Conversions {
	def inchesToCentimeters(value: Double)={
		// 1 inch = 2.54 
		value * 2.54
	}
	def gallonsToLiters(value: Double)={
		// 1 gallon = 3.78541 liters
		value * 3.78541
	}
	def milesToKilometers(value: Double)={
		// 1 mile = 1.60934 kms
		value * 1.60934
	}
}

// 2. The preceding problem wasn’t very object-oriented. Provide a general super- class UnitConversion and define objects InchesToCentimeters, GallonsToLiters, and MilesToKilometers that extend it.

abstract class UnitConversion {
	def convert(value: Double): Double
}

object inchesToCentimeters extends UnitConversion {
	def convert(value: Double)={value * 2.54}
}

object gallonsToLiters extends UnitConversion {
	def convert(value: Double)={value * 3.78541}
}

object milesToKilometers extends UnitConversion {
	def convert(value: Double)={value * 1.60934}
}

// 4. Define a Point class with a companion object so that you can construct Point instances as Point(3, 4), without using new.

class Point private (val x: Int, val y: Int) {
}

object Point {
	def apply(x: Int, y: Int) = new Point(x, y)
}

// 5. Write a Scala application, using the App trait, that prints its command-line arguments in reverse order, separated by spaces. For example, scala Reverse Hello World should print World Hello.

object reverseLine extends App {
	for (arg <- args.reverse) print(arg + " ")
}

object cardColor extends Enumeration {
	type cardColor = Value
	val club = Value("♣")
	val spade = Value("♠") 
	val diamond = Value("♦")
	val heart = Value("♥")
}


object rgbColorCube extends Enumeration {
	val black = Value(0x000000, "Black")
	val white = Value(0xffffff, "White")
	val red = Value(0xff0000, "Red")
	val yellow = Value(0xffff00, "Yellow")
	val green = Value(0x00ff00, "Green")
	val blue = Value(0x0000ff, "Blue")
}