Generic value-classes in Scala

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Let's say I have a type Pos (for position). In order to gain type-safety the column/row is not represented as Int but by types Col (column) and a Row:

case class Pos(col: Col, row: Row) {
  def +(other: Pos): Pos = Pos(col + other.col, row + other.row)
}

It's possible to add two positions, which consists of summing columns and rows respectively.

The definition of types Col and Row would look like this:

object Row {
  def apply(value: Int) = new Row(value)
  val zero = new Row(0)
}

object Col {
  def apply(value: Int) = new Col(value)
  val zero = new Col(0)
}

class Row(val value: Int) extends AnyVal {
  def +(other: Row): Row = Row(this.value + other.value)
}

class Col(val value: Int) extends AnyVal {
  def +(other: Col): Col = Col(this.value + other.value)
}

This is all fine, but I have the feeling of repeating myself. The definitions are almost identical.

Could I do something to generalize them?

asked 23 secs ago

Sebastian N.

741

Generic value-classes in Scala