C++学习

namespace std {
    template<>
    struct hash<FlexLength>{
        size_t operator()(const FlexLength &length) const {
            NSUInteger subhashes[] = {
                std::hash<int>()(length.type),
                std::hash<float>()(length.value),
            };
            return VZ::Hash::IntegerArrayHash(subhashes, sizeof(subhashes) / sizeof(subhashes[0]));
        }
    };
}

template http://blog.sina.com.cn/s/blog_74a271040100tkmj.html
操作符重载