copy constructor in object declaration and return from function

can't we simply overload "=" operator to instead of using copy constructor in object declaration and return from function ie in

someclass X = Y;
X=somefunction();

can I overload "=" operator in someclas开发者_高级运维s and not provide a copy constructor.

Is there any case which requires both copy constructor and overloading "=" operator to avoid pointer variables from two seperate objects to point to same memory location?

No, those are different concepts and both of them exist for performance reasons.

• Copy constructor is used when you create a new object (from an existing object).
• Assignment is used when the object already exists but you want to assign a new value to it.

If you provide one of them provide the other one as well.