How can I have a pointer to default struct object in a single statement?

Question

I can first get a default struct object and then a pointer to it. But I suspect there must be some graceful way to do it; probably in a single statement.

auto defaultStructObject = SomeStruct{};
auto pointerToDefaultStructObject = &defaultStructObject;

Are you trying to eliminate the line `auto defaultStructObject = SomeStruct{};` and you just want a pointer? — NathanOliver, Oct 21 '21 at 16:00
`SomeStruct{};` is a rvalue you need to extend it's life or it will be destroyed at the end of the full expression; if you could take it's address you would get a dangling pointer. You can extend it's life with an rvalue reference or a const reference eg `auto && refToDefaultStructObject = SomeStruct{};` — Richard Critten, Oct 21 '21 at 16:03
If your class has no arg constructor you can probably do this auto* pointerToMyStructObj = new MyStruct{}; — Angelos, Oct 21 '21 at 16:05

score 1 · Answer 1 · answered Oct 21 '21 at 20:33

1

auto defaultStructObject = SomeStruct{}, *pointerToDefaultStructObject = &defaultStructObject;

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answered Oct 21 '21 at 20:33

Remy Lebeau

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score 0 · Answer 2 · answered Oct 21 '21 at 16:19

You can probably use the first line inside the main function.

class MyClass {
    
    public:
    
    MyClass() {};
    void Print() const {std::cout << "hello world \n";}
};

int main() {
   
    auto* pObj = new MyClass();
    pObj->Print();
    return 0;
}

How can I have a pointer to default struct object in a single statement?

2 Answers2