[Boost-users] Re: enable_if for function templates

Agoston Bejo wrote:

Hi all, I am trying to enable only two version of a function. The caller may choose one

of the two versions by specifying a template parameter. I've got two versions

#include <iostream> #include #include

using namespace std; using namespace boost;

template enable_if_c f(T t) { cout << 1 << endl; }

template enable_if_c f(T t) { cout << 2 << endl; }

int _tmain(int argc, _TCHAR* argv[])

_tmain, _TCHAR ... what are these funny symbols? ;-)

{ f<1>(10); // ERROR f<2>(5.5); // ERROR f<3>(7); // ERROR return 0; }

I'd say enable_if is not the right tool for this situation. Try: template<int N> struct f_impl { template<typename T> static void execute(T t) { cout << "f_impl::execute()" << "\n"; } }; template void f(T t) { f_impl<N>::execute(t); } template<> struct f_impl<1> { template<typename T> static void execute(T t) { cout << "1" << "\n"; } }; template<> struct f_impl<2> { template<typename T> static void execute(T t) { cout << "2" << "\n"; } }; int main() { f<1>(10); f<2>(5.5); f<3>(7); return 0; } Jonathan