Functions

- [Instructor] Std::function also comes…from the functional header.…It is a wrapper for invokable objects…which includes functions, function objects,…also known as functors, and lambdas.…We can also store wrapped invokable objects…in a vector of function objects.…Let's take a look at some code to see how.…Again, we're going to start off with a file…that already includes our header.…So we've got functional, iostream, string, and vector.…We're using a namespace std.…And we're going to start up here, and we need to create…a few helper functions to get ourselves going.…

So the first one's going to be a void,…and it's going to be called demoFunction.…It doesn't take any parameters.…And the only thing this function does is call cout,…and it let's us know that demoFunction was called.…And then we do an endl, and that's the end of that.…The next function that we have here…is we're going to say void and call this function adder.…And it's going to take an int a and an int b.…

And once again it's going to do a cout,…and it's going to say Called adder comma a,…