I get an error saying type N is unused or used in non-specializable positions.
, for the method with the following signature:
protected def offsetFrom0[@specialized(Int,Long) N](offsetFrom1 : Codec[N])(implicit N : Integral[N]) : Codec[N]
Can someone explain to me in layman's terms what the rules are around specialization?
The @specialized
annotation can be used both for class and method type parameters.
def gethead[@specialized(Int,Float,Double) T: Numeric](items: T*): T = items(0)
gethead(4,57,32) // Result: 4
So in your case you can do something along the lines of:
case class Offset[@specialized(Int, Long) N](offsetFrom1: N) {
def offsetFrom0: N = ???
}
Offset(1).offsetFrom0
Offset(1L).offsetFrom0