How Does the `override` Keyword in C Ensure Correct Virtual Function Overriding?

How the 'override' Keyword Enforces Virtual Function Overriding

The C 11 override keyword is more than just a check for a overridden virtual method in the base class, it is a declaration that the function it precedes is intended to override a virtual function in the base class. This explicit declaration serves to:

Ensure the intended override:
The override keyword ensures that the function being defined is actually intended to override a virtual function in the base class. If it is not, the compiler will flag an error, alerting the programmer to the discrepancy and preventing unintended behavior.

Example:
`
struct Base { virtual int foo() const; };

struct Derived : Base {

virtual int foo() override { //whoops!
    // ...
}

};
`
Here, the whoops! comment highlights a mistake - the function foo() is declared virtual in Derived but without const, which conflicts with the const declared in Base. If override were not used, this error would go unnoticed.

Avoid Silent Overriding Errors:
Without the override keyword, the absence of an override function in the derived class would result in silent errors. The compiler would treat the function as a new declaration, leading to unexpected consequences. Override eliminates this problem by explicitly stating the intended override, thus preventing these errors.

Enhanced Readability and Error Checking:
The override keyword enhances the readability of code, making it clear which functions are intended to override base class methods. Additionally, it enables more rigorous error checking during compilation, helping identify and prevent potential issues from the outset.

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