TicTacToe.scala

sealed trait Mark
case object Circle extends Mark
case object Cross extends Mark

case class Board(array: Array[Array[Mark]]) {
  
  lazy val cols: Array[Array[Mark]] = {
    val col1 = Array(array(0)(0), array(1)(0), array(2)(0))
    val col2 = Array(array(0)(1), array(1)(1), array(2)(1))
    val col3 = Array(array(0)(2), array(1)(2), array(2)(2))

    Array(col1, col2, col3)
  }

  lazy val firstRow = array(0)
  lazy val secondRow = array(1)
  lazy val thirdRow = array(2)

  lazy val firstCol = cols(0)
  lazy val secondCol = cols(1)
  lazy val thirdCol = cols(2)

  lazy val firstCross = Array(firstRow(0), secondRow(1), thirdRow(2))
  lazy val secondCross = Array(firstRow(2), secondRow(1), thirdRow(0))
}

object Check {

  def inRows(board: Board, mark: Mark): Boolean = {
    lazy val inRow1 = board.firstRow.forall(_ == mark)
    lazy val inRow2 = board.secondRow.forall(_ == mark)
    lazy val inRow3 = board.thirdRow.forall(_ == mark)

    inRow1 || inRow2 || inRow3
  }

  def inCols(board: Board, mark: Mark): Boolean = {
    lazy val inCol1 = board.firstCol.forall(_ == mark)
    lazy val inCol2 = board.secondCol.forall(_ == mark)
    lazy val inCol3 = board.thirdCol.forall(_ == mark)

    inCol1 || inCol2 || inCol3
  }

  def inCross(board: Board, mark: Mark): Boolean = {
    lazy val inCross1 = board.firstCross.forall(_ == mark)
    lazy val inCross2 = board.secondCross.forall(_ == mark)

    inCross1 || inCross2
  }

}

val array: Array[Array[Mark]] = Array(
  Array(Cross, Cross, Cross), 
  Array(Cross, Cross, Circle),
  Array(Cross, Circle, Cross)
)

assert(Check.inRows(Board(array), Cross) == true)
assert(Check.inCols(Board(array), Cross) == true)
assert(Check.inCross(Board(array), Cross) == true)
assert(Check.inCross(Board(array), Circle) == false)