Generalized type constraints example

PrintFormatter.scala

case class PrintFormatter[T](item : T) {
	def formatString(implicit evidence: T =:= String) = { // Will only work for String PrintFormatters
    	println("STRING specialised printformatting...")
	}
    def formatPrimitive(implicit evidence: T <:< AnyVal) = { // Will only work for Primitive PrintFormatters
		println("WRAPPED PRIMITIVE specialised printformatting...")
	}
}

val stringPrintFormatter = PrintFormatter("String to format...")
stringPrintFormatter formatString
// stringPrintFormatter formatPrimitive		// Will not compile due to type mismatch

val intPrintFormatter = PrintFormatter(123)
intPrintFormatter formatPrimitive
//  intPrintFormatter formatString			// Will not compile due to type mismatch