Is the 'override' keyword just a check for a overridden virtual method?

c++ c++11 overriding virtual-functions c++-faq
aiao picture aiao · Dec 14, 2012 · Viewed 45.9k times · Source

As far as I understand, the introduction of override keyword in C++11 is nothing more than a check to make sure that the function being implemented is the overrideing of a virtual function in the base class.

Is that it?

Answer

Kerrek SB picture Kerrek SB · Dec 14, 2012

That's indeed the idea. The point is that you are explicit about what you mean, so that an otherwise silent error can be diagnosed:

struct Base
{
    virtual int foo() const;
};

struct Derived : Base
{
    virtual int foo()   // whoops!
    {
       // ...
    }
};

The above code compiles, but is not what you may have meant (note the missing const). If you said instead, virtual int foo() override, then you would get a compiler error that your function is not in fact overriding anything.

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