c++ - error: boost.fusion::for_each() and struct derived from boost.tuple -

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on compilation code:

struct any_type: boost::tuple<std::string, std::string, std::string> {    ... };  struct functor {    void operator()(const std::string& v) {       std::cout << v << std::endl;    } };  int main() {    any_type type;    boost::fusion::for_each(type, functor()); }

get error: no type named 'category' in 'struct any_type' why? want inherit boost.tuple.

inherit boost::fusion::tuple instead of boost::tuple.
note: consider making void operator()(const std::string& v) const


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