c++ - Non-type template parameter for polymorphic lambda? -

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is possible write this?

[](std::index_sequence<std::size_t ...i> s) {  };

or this?

[]<std::size_t ...i>(std::index_sequence<i...> s) {   }

how syntax in c++14 or c++17? or not possible @ all? basically, want have i template parameter pack, , lambda serves way that. alternatively, there syntax achieve following?

std::index_sequence<std::size_t ...i> x = std::make_index_sequence<10>{};  // local template parameter pack

gcc provides latter syntax as extension, it's not standard:

template <typename... ts> void foo(const std::tuple<ts...>& t) {     auto l = [&t]<std::size_t ...i>(std::index_sequence<i...> s) {          std::initializer_list<int>{ (std::cout << std::get<i>(t), 0)... };     };      l(std::index_sequence_for<ts...>{}); }

live demo


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