How to initialize an object reference in C ++?

Question

I tried to do

MyClass& x;
x = MyClass(a,b,c);

But C ++ will not let me do this because it believes that x is not initialized at the beginning.

So I tried to do

MyClass& x = MyClass(a,b,c);

But an error occurred, saying invalid initialization of non-const reference of type 'MyClass&' from an rvalue of type 'MyClass'

What about him? It seems I just can’t do anything now. How do I solve the initialization problem?

Answer 1

The link must reference an existing object. Therefore, before you can access it, you must first create an object.

MyClass y = MyClass(a,b,c);
MyClass &x = y;

Answer 2

A regular reference to constshould not be initialized with an lvalue expression (essentially an expression that refers to a memory location), for example

MyClass o{ a, b, c };
MyClass& r = o;

const, rvalue ( &&), rvalue, , :

MyClass const& rc = foo();
MyClass&& rr = foo();

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