http://stackoverflow.com/questions/15079444/how-to-deep-copy-classes-with-traits-mixed-in

copy_with_traits.scala

abstract class A {
  type Self <: A

	def x: Any

	def copy(): Self = {
		val copy = construct()
		copyStateTo(copy)
		copy
	}
	
	protected def construct(): Self
	protected def copyStateTo(obj: Self) {}
	
	override def toString = s"A(x = $x)"
}

abstract class IntA extends A {
	type Self <: IntA
	
	override def x: Int
	override def toString = s"IntA(x = $x)"
}

abstract class StringA extends A {
	type Self <: StringA

	override def x: String
	override def toString = s"StringA(x = $x)"
}

case class B(x: Int) extends IntA {
	type Self = B
	protected def construct() = B(x)
	override def toString = s"B(x = $x)"
}

trait T1 extends A {
	type Self <: T1
	
	var foo = 0

	def incFoo() {
		foo = foo + 1
	}

	override def copyStateTo(obj: Self) {
		super.copyStateTo(obj)
		obj.foo = foo
	}
	
	override def toString = s"${super.toString}\n  with T1(foo = $foo)"
}

trait T2 extends A {
	type Self <: T2

	var bar = 0.9

	def squareBar() {
		bar = bar * bar
	}

	override def copyStateTo(obj: Self) {
		super.copyStateTo(obj)
		obj.bar = bar
	}
	
	override def toString = s"${super.toString}\n  with T2(bar = $bar)"
}

class IntAWithT1(val x: Int) extends IntA with T1 {
	type Self = IntAWithT1
	override def construct() = new IntAWithT1(x)
}

class StringAWithT2WithT1(val x: String) extends StringA with T2 with T1 {
	type Self = StringAWithT2WithT1
	override def construct() = new StringAWithT2WithT1(x)
}

val b = new B(-1)
val iat1 = new IntAWithT1(10)
val sat2t1 = new StringAWithT2WithT1("str")

println(b)
	// B(x = -1)
	
println(iat1)
	// IntA(x = 10)
		// with T1(foo = 0)

println(sat2t1)
// StringA(x = str)
  // with T2(bar = 0.9)
  // with T1(foo = 0)
	
iat1.incFoo()
sat2t1.squareBar()
sat2t1.incFoo()
sat2t1.squareBar()
sat2t1.incFoo()

println(iat1)
	// IntA(x = 10)
		// with T1(foo = 1)
println(sat2t1)
	// StringA(x = str)
		// with T2(bar = 0.6561000000000001)
		// with T1(foo = 2)
		
val bC: IntA = b.copy()
println(b)
	// B(x = -1)
	
val iat1C: IntA with T1 = iat1.copy()
println(iat1C)
	// IntA(x = 10)
		// with T1(foo = 1)
		
val sat2t1C: StringA with T2 with T1 = sat2t1.copy()
	// println(sat2t1C)
		// with T2(bar = 0.6561000000000001)
		// with T1(foo = 2)