Returning From a Void Function in C++

Question

Consider the following snippet:

void Foo()
{
  // ...
}

void Bar()
{
  return Foo();
}

What is a legitimate reason to use the above in C++

Answer 1

Probably no use in your example, but there are some situations where it's difficult to deal with void in template code, and I expect this rule helps with that sometimes. Very contrived example:

#include 

template 
T retval() {
    return T();
}

template <>
void retval() {
    return;
}

template <>
int retval() {
    return 23;
}

template 
T do_something() {
    std::cout << "doing something\n";
}

template 
T do_something_and_return() {
    do_something();
    return retval();
}

int main() {
    std::cout << do_something_and_return() << "\n";
    std::cout << do_something_and_return() << "\n";
    do_something_and_return();
}

Note that only main has to cope with the fact that in the void case there's nothing to return from retval . The intermediate function do_something_and_return is generic.

Of course this only gets you so far - if do_something_and_return wanted, in the normal case, to store retval in a variable and do something with it before returning, then you'd still be in trouble - you'd have to specialize (or overload) do_something_and_return for void.