Comma omitted in variadic function declaration in C++

Question

I am used to declaring variadic functions like this:

int f(int n, ...);

When reading The C++ Programming Language I found that the dec

Answer 1

Currently, both of these declarations have the same meaning:

int f(int n, ...);
int f(int n ...);

This leads to an issue where the following two declarations are both legal, yet have wildly different meanings:

template  void f(T...); // function template with parameter pack
template  void f(T...);    // variadic function

Once C++11 introduced variadic templates, it is much more likely that the second declaration is a programmer error rather than lazily omitting the comma. As a result, there was a proposal to remove the latter from the language (P0281), but it was apparently rejected.