Overloading operator=

[Duki]

Is there any reason to check for self assignment, if you're not using array's or pointers, when overloading the = operator?

For example, if the only datatypes in Vehicle are int cylinders and string manufacturer, do I really need to check before assigning? If so, what's the point?

[Dave Sinkula]

http://new-brunswick.net/workshop/c++/faq/assignment-operators.html

Obviously no one ever explicitly does a self assignment like the above, but since more than one pointer or reference can point to the same object (aliasing), it is possible to have self assignment without knowing it:

[vijayan121]

> if the only datatypes in Vehicle are int cylinders and string manufacturer, do I really need to check before assigning?
you really do not need to write an assignment operator at all; the compiler will synthesize a (non-trivial) assignment operator with the correct semantics.

> If so, what's the point?
only efficiency (avoid the call to string's operator=, which would check for a self assignment in any case).