[問題] &operator vs operator
class point
{
private:
bool changed;
double data[3];
public:
double &operator [](int i)
{
changed = true;
return data[i];
}
double operator [](int i) const
{
return data[i];
}
}
重載了兩個operator []，
主要是希望程式可以判別出
point[0] = 5;//changed = true
double x = point[0];
的不同，
但程式現在即使是
x = point[0];
他也是呼叫
double &operator [](int i)
請問 class 可以做出此功能嗎？
判別資料是否發生改變
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class point{
proxy & oprator[] (int n){
return proxy(data[n]，changed)
}
}
class proxy class{
private:
bool *changed;
double *data;
public:
proxy(double &d,bool &b){
data = &d;
changed = &b;
}
proxy &oprator = (double d){
*changed = true;
*data = double;
return this;
}
double operator (double){
return *data;
}
}
除
operator =, operator double
之外，
還必須自己重寫
operator +-×÷
+=，-=，…
等運算吧？
(抱歉，我還沒試這邊)
這些介面操作方法，
會讓class變的需更多時間
在建構/解構上嗎
※ 編輯: noodleT (110.26.71.227), 12/01/2015 21:57:45
※ 編輯: noodleT (110.26.71.227), 12/01/2015 22:02:04
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