【Swift】配列をコンソールにテーブル形式で表示する 👉 https://android.benigumo.com/20240213/show-table/

showtable.swift

extension Array where Element: Collection, Element.Index == Int {
  func showTable() {
    transposed()
      .map { $0.map { "\($0)" } }
      .map {
        let max = $0.map { $0.countAsHalfWidth }.max()!
        return $0.map { $0.padding(length: max) }
      }
      .transposed()
      .map { "| " + $0.joined(separator: " | ") + " |" }
      .forEach {
        print($0)
      }
  }

  func transposed() ->  [[Element.Element]] {
    let cols = 0 ..< (self.first?.count ?? 0)
    let rows = 0 ..< self.count
    return cols.map { col in
      rows.map { row in
        self[row][col]
      }
    }
  }
}

extension String {
  var countAsHalfWidth: Int {
    return Array(self)
      .map { $0.isASCII ? 1 : 2 }
      .reduce(0, +) // sum
  }

  func padding(length: Int, pad: String = " ") -> String {
    return String(
      repeating: pad,
      count: length - countAsHalfWidth
    ) + self
  }
}


// ex.
let data = [
  [1, 2, 3],
  ["いぬ", "ねこ", "さる"],
  ["dog", "cat", "monkey"]
]

print(data)
// [[1, 2, 3], ["いぬ", "ねこ", "さる"], ["dog", "cat", "monkey"]]

data.showTable()
// |    1 |    2 |      3 |
// | いぬ | ねこ |   さる |
// |  dog |  cat | monkey |