I made my constructor private in this example because I was trying to ensure that the class instances could ONLY be created as part of shared_ptrs or unique_ptrs, thus eliminating inadvertant creation of instances in other ways.So if I have to make the constructor public, can anyone ...
在实际操作中,我们还遇到了一种特殊的情况:假设有一个类Widget的构造函数是private的,我们想在它的friend函数中动态创建一个Widget对象并移入智能指针: class Widget { friend void fun(); // private constructors Widget() = default; Widget(int) {} Widget(double, double) {} Widget(const std::string ...
make_shared虽好, 但也存在一些问题, 比如, 当我想要创建的对象没有公有的构造函数时,make_shared就无法使用了, 当然我们可以使用一些小技巧来解决这个问题, 比如这里How do I call ::std::make_shared on a class with only protected or private constructors? 对象的内存可能无法及时回收 make_shared只分配...
#include <iostream> #include <memory> class Foo : public std::enable_shared_from_this<Foo> { private: //the user should not construct an instance through the constructor below. Foo(int num):num_(num) { std::cout << "Foo::Foo\n"; } public: Foo(const Foo&) = delete; Foo(Foo&&...
// it's from this line that comes the need to have the constructor protected, not private: make_unique_enabler(Args &&... args) : ClassWithProtectedCtor(std::forward<Args>(args)...) {} }; return std::make_unique<make_unique_enabler>(std::forward<Args>(args)...); ...
make_shared 虽好, 但也存在一些问题, 比如, 当我想要创建的对象没有公有的构造函数时, make_shared 就无法使用了, 当然我们可以使用一些小技巧来解决这个问题, 比如这里 How do I call ::std::make_shared on a class with only protected or private constructors?...
is there a reason why std::make_shared would require a default constructor? 我试图找出这是否是谷物的要求。 我一直在收到错误,因为类构造器(默认构造器)是私有的,我将其放置在这里是有原因的。 但是,错误的始发行似乎是std :: make_shared,而不是谷物,后者需要默认构造函数,但已经是一个朋友类,因此应该...
我让它变得简单，并将所有代码放在一个文件中，即使它的结构是在两个文件中。为了清楚起见，我不得不...
问如何阻止std::make_shared<T>的使用EN在C++中，阻塞T类型的用户堆分配实际上不是一件可以做的事情...
I made my constructor private in this example because I was trying to ensure that the class instances could ONLY be created as part of shared_ptrs or unique_ptrs, thus eliminating inadvertant creation of instances in other ways.So if I have to make the constructor public, can anyone ...