美學為何重要

class StatsKeeper{
public:
//記錄倍精度數列的類別
  void Add(double d);  //以及快速統計的方法
 private: int count;    /*到目前的數 量
*/ public:
     double Average();
     
private: double minimum;
list<double>
  past_items
      ;double maximum;
};

//記錄倍精度數列的類別以及快速統計的方法
class StatsKeeper{
  public:
    void Add(double d);
    double Average();
  private:
    list<double>pass_times;
    int count;  //到目前的數量
    
    double minimum;
    double maximun;
 };

顯然第2個程式碼賞心悅目許多且更容易閱讀。

調整斷行讓程式更加一致與整潔

為了計算程式在各種網路連線速度下的行為，建立了 TcpConnectionSimulator 類別，建構子需要4個參數：

1. 連線速度(Kbps)
2. 平均延遲(ms)
3. 延遲的變化(jitter，ms)
4. 丟包率(packet loss，百分比)

public class PerformanceTester{
  public static final TcpConnectionSimulator wifi = new TcpConnectionSimulator(
      500， /*kbps*/
      80, /*millisecs latency*/
      200, /*jitter*/
      1 /*packet loss%*/);
  public static final TcpConnectionSimulator t3_fiber = 
    new TcpConnectionSimulator(
      45000, /*kbps*/
      10, /*millisecs latency*/
      0, /*jitter*/
      0 /*packet loss%*/);
  public static final TcpConnectionSimulator cell = new TcpConnectionSimulator(
      100， /*kbps*/
      400, /*millisecs latency*/
      250, /*jitter*/
      5 /*packet loss%*/);
}

我們讓程式碼一致，加入幾個換行，並將註解移到上方，所有參數移到同一行：

public class PerformanceTester{
  //TcpConnectionSimulator(throughput,latency,jitter,packet_loss)
                              [Kbps]   [ms]    [ms]    [percent]
  public static final TcpConnectionSimulator wifi=
      new TcpConnectionSimulator(500,    80,   200,   1);
  public static final TcpConnectionSimulator t3_fiber=
      new TcpConnectionSimulator(4500,   10,     0,   0);
  public static final TcpConnectionSimulator cell=
      new TcpConnectionSimulator(100,   400,   250,   5);
}

Reference

• <<易讀程式之美學－提升程式碼可讀性的簡單法則 >>(The Art of Readable Code)