code: function compile(pos) {
    var values = []
  
    if (!pos) {
      return null
    }
  
    values = [[pos.line || 1, pos.column || 1].join(':')]
  
    if ('offset' in pos) {
      values.push(String(pos.offset || 0))
    }
  
    return values
  }
docs: Compile a single position.