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c++singleton

does c++ singleton create new instance every time?

C++ singleton code looks like this:

MyClass& MyClass::getInstance(){
    static MyClass instance;
    return instance;
}

Looking specifically at static MyClass instance;

Is a new instance created each time getInstance is called?

EDIT

I understand that static members are one-per-class. But doesn’t static MyClass instance re-declare (and therefore re-create) the “single” instance instance each time getInstance() is called?

Solution

  • Because the MyClass member variable is declared as static and you are returning a reference to it, not a copy. Static member variables are not created per-object like normal member variables; rather, there is one instance of the variable accessible from all objects of the class.

    See here.