Re: [boost] [Ann] Variadic Templates

From: Thorsten Ottosen (thorsten.ottosen_at_[hidden])
Date: 2006-08-07 16:05:25

Hi Doug,

First, let me say it is really nice to see this implemented.

>    template<typename T, typename... Args>
>    void printf(const char* s, const T& value, const Args&... args) {
>      while (*s) {
>        if (*s == '%' && *++s != '%') {
>          std::cout << value;
>          return printf(++s, args...);
>        }
>        std::cout << *s++;
>      throw std::runtime_error("extra arguments provided to printf");
>    }
> 

> Are variadic templates worthwhile? Will they help us build better,  
> cleaner Boost libraries in the future?

I think the answer to that is definitely yes. There's quiye a few 
libraries in boost that use the preprocessor in lack of something better.

> Should we bring variadic  
> templates to the C++ committee, 

It does seem to simplify quite a few libraries, doesn't it.

As for the printf-example, then it might be reasonable to consider 
code-bloat a little. If you don't watch out a little, it might generate 
a lot of code.

-Thorsten