Generating a sequence of zeros at compile time

Question

I have the following problem:

template< size_t... N_i >
class A
{
  public:

    // ...

    void foo()
    {
      bar( /* 0,...,0 <- sizeof...(N_i) many */);
    }
};

I want to call a function bar and pass sizeof...(N_i) many arguments to it which are all zeros, e.g., bar(0,0,0) in case sizeof...(N_i) == 3. How can this be implemented?

Answer 1

bar(((void)N_i, 0)...);

The comma operator will discard N_i, yielding just the right-hand operand's value (0). The cast is to prevent a warning about N_i being discarded.