函数重载，只有c ++中的纯虚函数中的“ uint32_t”和uint64_t”发生了变化

Question

I've a pair pure virtual function defined inside a c++ class, which I've overloaded. Code snippet below::

virtual uint64_t Abc::GetValue()=0; 
virtual uint32_t Abc::GetValue()=0;

Here, the only difference in function signature is the return type of GetVal() " uint32_t " & " uint64_t "..

It's throwing compilation error that this can't be overloaded.

Plz help me on this.

Answer 1

You can't overload based on return type, only on parameter types. This is because the overload is chosen based on how the function is called, and a function call doesn't specify the expected return type.

Options include:

• Give the functions different names;
• "return" the value via a reference parameter, rather than the return value;
• add a dummy parameter, with a different type for each version, to specify the return type;
• return a "proxy" object that's convertible to either type (although this means you'll only have a single function, so derived classes can't override the two versions separately).

Answer 2

In c++ onverloading is only done on the parameters of the function not on the return type . So your are redefining the same function which is an error.