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C++标准类别违约构造者
原标题:Disable the default constructor of a standard class in C++
  • 时间:2023-12-16 02:35:37
  •  标签:
  • c++

是否有办法消除使用C++标准班级的违约构造?

例如,我谨表示不赞成使用<代码>的违约构造:optional<T>,以便小组成员必须明确说明该标的是否用nullopt建造。 或整个代码基的价值。

除撰写文字检查外,C++语言是否提供了解决办法?

问题回答

在C++中,你可以通过使用<代码> 删除 syntax 宣布其为删除而宣布使用违约构造。 然而,铭记这种做法将使这一类人无法构造,因此,在不提供明确价值观的情况下,不可能制造一些事例。

关于<代码>std:optional<T>,你可以宣布从以下表格中删除的违约构造:optional<T>:

#include <optional>

template<typename T>
class MyOptional : public std::optional<T> {
public:
    MyOptional() = delete;  // Disabling the default constructor
    using std::optional<T>::optional;  // Inheriting other constructors
};

int main() {
    // MyOptional<int> obj;  // This line would result in a compilation error
    MyOptional<int> objWithValue(42);  // This is allowed
    return 0;
}

在这种例子中,试图利用违约建筑商创建<代码>MyOptional<int>将造成汇编错误。

Remember, this approach makes your class non-default-constructible, so you will need to provide values explicitly during instantiation.





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