Type aliasing and implicit conversions in harmony

This topic combines advanced two topics. types and implicit methods. This topic is not really intended to be instructional as much as a illustration of the cool stuff you can do with the language. As always becareful not to cut yourself :-)

In keeping with the uniform principle of Scala, types can defined as variables. This is useful for several reasons but this topic covers a cool/fun effect of having types be declared like variables. Type Aliasing. In the example below an alias | is created for the Either class. This allows the | to be used in place of Either.

1. // Start of example 1.  creating the type alias
2. // define the | type
3. scala> type |[A,B] = Either[A,B]
4. defined type alias $bar
6. // If a Type has 2 parameters it can be used in operator form
7. scala> Array[Int | Long](Left(5),Right(12L))
8. res0: Array[|[Int,Long]] = Array(Left(5), Right(12))
10. // start of example 2.  Simplify creation of an Array (or other collection) of either
11. scala> implicit def makeLeft[A,B](a:A):Either[A,B] = Left(a)
12. makeLeft: [A,B](a: A)Either[A,B]
14. scala> implicit def makeRight[A,B](b:B):Either[A,B] = Right(b) 
15. makeRight: [A,B](b: B)Either[A,B]
17. // Since there are implicits to convert to Right and Left the values in the Array will be wrapped
18. // automatically.  Makes the syntax MUCH cleaner and easier to read.
19. scala> Array[Int|String](5,"Wurst",123,2,6)
20. res1: Array[|[Int,String]] = Array(Left(5), Right(Wurst), Left(123), Left(2), Left(6))