Menu
An inline function is one for which the compiler copies the code from the function definition directly into the code of the calling function rather than creating a separate set of instructions in memory.
If you need to explicitly declare inline function in the class then just declare the function inside the class and define it outside the class using inline keyword.
Inline function in C++ is an enhancement feature that improves the execution time and speed of the program. The main advantage of inline functions is that you can use them with C++ classes as well.
The inline keyword tells the compiler to substitute the code within the function definition for every instance of a function call. Using inline functions can make your program faster because they eliminate the overhead associated with function calls.
That sounds like two totally unrelated things. Putting inline at both the declaration in the class and the definition outside of the class is not needed. Putting it at one of the declarations is enough.
If you talk about adding inline in a .cpp file where a function is defined there, and that function is a public member, then you should not do that. People who call inline functions must have their definitions visible to them. The C++ Standard requires that.
By marking it inline, you are saying that this method will be executed much faster than a non-inline method, and that callers don't have to worry about excessive calls to the method.
That's nonsense. Marking a function inline doesn't guarantee that the function will actually be physically inlined; even if it is, that's no guarantee that your function will be "faster".
By marking the definition inline as well as the declaration, you're just confusing things by pretending to your user that there's any guarantee about anything, which there isn't...
If I am a user of a class, do I really care about excessive calls to the method?
Not really.
In fact, really, the only time you should write inline is when you need to force inline storage for some reason (regardless of whether inlining occurs, using the keyword always affects the application of the one-definition rule to your function… though requiring this is rare); otherwise, let the compiler decide which functions to inline, and move on. The corollary of this is that you don't need to worry about using the keyword to pretend that it's documenting anything.
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With