Recursive Fibonacci using tail recursion

Fib.scala

def fib( n: Long ):Long = {		
	def fib_tailrec( n:Long, a:Long, b:Long ):Long = {
		n match {
			case 0 => a			
			case _ => fib_tailrec( n - 1, b, a + b )
		}	
	}

	fib_tailrec(n, 0, 1)		
}