Question

The code below don’t compile in vs 2012. In line 4 I got an error C2143: syntax error : missing ‘,’ before ‘<‘. Can somebody help me to fix it. I would be very appreciate.

ps. dont’ focus on case insensitive, i have delete something to make the code simpler.

#include<functional>

template<typename Ty>
struct case_insensitive_less : public binary_function<Ty, Ty, bool>{
    bool operator()(Ty const& left, Ty const& right) const
    {
        return (left < right);
    }
};

int main(){}

Answer 1

You need the std namespace:

std::binary_function

Note that std::binary_function is deprecated in C++11. If you have C++11 support, consider using std::function and/or lambdas.