compile-time string hashing

Question

I need to use a string as the ID to obtain some object. At implement this in a run-time, and works well. But this makes the static type checking impossible, for obvious rea

Answer 1

Solution with gcc-4.6:

#include 
template
struct hash_calc {
    static constexpr size_t apply (const char (&s)[N]) {
       return  (hash_calc::apply(s) ^ s[I]) * 16777619u;
    };
};

template
struct hash_calc {
    static constexpr size_t apply (const char (&s)[N]) {
       return  2166136261u;
    };
};

template
constexpr size_t hash ( const char (&s)[N] ) {
    return hash_calc::apply(s);
}

int main() {
   char a[] = "12345678";
   std::cout << std::hex << hash(a) << std::endl;
   std::cout << std::hex << hash("12345678") << std::endl;
}

http://liveworkspace.org/code/DPObf

I`m happy!