I am trying to build a Tic Tac Toe, the method `valid_move?` suppose to make sure the submitted position is: 

1. Present on the game board.
2. Not already filled with a token.

So I first tried to make sure the position is between 1-9 on the board, and second tried to make sure the position is not taken, here i just use a **helper method** `position_taken?` but seems something is wrong and my `valid_move?` is not working....

```
def valid_move?(board,position)
  if  position.to_i.between?(1,9) && position_taken?
    true
  else
     false
  end
end

def position_taken?(board,position)
  if board[position] == " "
    false
    elsif board[position] == ""
    false
    elsif  board[position] == nil
    false
    else   board[position] == "X" || "O"
    true

  end
end

```

basically im trying to pass below spec:

```
  it 'returns true for a valid position on an empty board' do
    board = [" ", " ", " ", " ", " ", " ", " ", " ", " "]
    position = "1"
    expect(valid_move?(board, position)).to be_truthy
  end

  it 'returns nil or false for an occupied position' do
    board = [" ", " ", " ", " ", "X", " ", " ", " ", " "]
    position = "5"

    expect(valid_move?(board, position)).to be_falsey
  end

  it 'returns nil or false for a position that is not on the board' do 
    board = [" ", " ", " ", " ", " ", " ", " ", " ", " "]
    position = 100

    expect(valid_move?(board, position)).to be_falsey
  end

end

```