Using lambda as an argument : std::function or template?

I'm studying c++11 especially interested in lambda. After some practices, I assumed that lambda closure is an nameless function object. So I wrote this code. ``` template <class callable_object> void lambda_caller( callable_object lambda ) { std::cout<< sizeof(lambda) << endl; lambda(); } ``` I know that I can use `std::function` instead of using template, but I don't want the overhead while typecasting. But I found one problem reading this question : Why can't I create a vector of lambda in C++11? The answerer said, "Every lambda has a different type- even if they have the same signature.". Compilers makes different codes for different classes. So I think that my compiler will make another version of `lambda_caller` whenever I make another definition of lambda to pass. Is there any way to avoid it, except using `std::function`? Isn't there any generic type for lambda closure?