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構文のnestを深くしたく無い時の[if not] or [unless]的な書き方

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メモ代わりに。
swift勉強中に以下の様なサンプルコードが出てきたのだが、構文のnestを深くしたくなかった。

# ViewController内のコードと思って頂ければ。

func hoge() {
    if let number = Int(hogeTextField.text!) =  {
      print(number)
      // ここに色々処理   
    }
}

ので[if not] or [unless]的な書き方が無いか検索したらguard statementというのが出てきた。
これを使えば以下の用に書ける。

# ViewController内のコードと思って頂ければ。

func hoge() {
    guard let number = Int(hogeTextField.text!) else {
        return
    }

    print(number) // ブロックの外でもちゃんと使用可能
    // ここに色々処理  
}

便利!

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