Coworker asked if I knew how to do a "for" with C macros, to avoid manually instantiating lots of helper functions. Here's a template metaprogramming-based solution, wich creates an array-like struct that contains 500 pointers to function you can then call. Woot! Note that the maximum T allowed by clang is 512, while gcc sets the maximum at 500 …

templateLoop.cpp

#include <cstdio>

template <int T> void func(){printf("Number %d\n", T);}

typedef void (*functype)();

template <int T> struct funcs
{
    funcs<T-1> rest ;
    functype f ;
    funcs() : f( func<T> ) {}
    functype operator[](int i) { return reinterpret_cast<functype*>(this)[i] ; }
};

template <> struct funcs <0>
{
    functype f ;
    funcs() : f( func<0> ) {}
};

funcs<500> funcInstances ;

int main()
{
   for( int i = 0 ; i < 500; ++i )
       funcInstances[i]();
}