Functions with a variable number of arguments are called variadic functions. Function templates with a variable number of arguments are called variadic function templates. Knowledge of C++ variadic macros (va_start, va_end, va_arg and va_copy, va_list) is not necessary for learning how to write variadic function templates, but it represents a good starting point.

We have already used variadic templates in our previous recipes, but this one will provide detailed explanations.