How do I pass a C++11 random number generator to a function?

Question

Do they all inherit from a base class? Do I have to use templates?

(I am referring to these http://www.codeguru.com/cpp/cpp/cpp_mfc/stl/article.php/c15319/)

Answer 1

What worked for me was using an std::function:

#include 
#include 

void exampleFunction(std::function rnd) {
    auto randomNumber = rnd();
}

std::minstd_rand rnd;
exampleFunction([&rnd](){ return rnd(); });

// This won't work as it passes a copy of the object, so you end up with the same
// sequence of numbers on every call.
exampleFunction(rnd);

You're not really passing around the random object, just a method to call the object's operator (), but it achieves the same effect.

Note that here the precision of the random number generator's return value may be reduced as the std::function is declared as returning an int, so you may want to use a different data type instead of int depending on your need for precision.