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diff --git a/src/boost/libs/hana/example/tutorial/introspection.json.cpp b/src/boost/libs/hana/example/tutorial/introspection.json.cpp
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+++ b/src/boost/libs/hana/example/tutorial/introspection.json.cpp
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+// Copyright Louis Dionne 2013-2017
+// Distributed under the Boost Software License, Version 1.0.
+// (See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
+
+#include <boost/hana.hpp>
+
+#include <iostream>
+#include <string>
+#include <type_traits>
+#include <utility>
+namespace hana = boost::hana;
+using namespace std::literals;
+
+
+//! [utilities]
+template <typename Xs>
+std::string join(Xs&& xs, std::string sep) {
+  return hana::fold(hana::intersperse(std::forward<Xs>(xs), sep), "", hana::_ + hana::_);
+}
+
+std::string quote(std::string s) { return "\"" + s + "\""; }
+
+template <typename T>
+auto to_json(T const& x) -> decltype(std::to_string(x)) {
+  return std::to_string(x);
+}
+
+std::string to_json(char c) { return quote({c}); }
+std::string to_json(std::string s) { return quote(s); }
+//! [utilities]
+
+//! [Struct]
+template <typename T>
+  std::enable_if_t<hana::Struct<T>::value,
+std::string> to_json(T const& x) {
+  auto json = hana::transform(hana::keys(x), [&](auto name) {
+    auto const& member = hana::at_key(x, name);
+    return quote(hana::to<char const*>(name)) + " : " + to_json(member);
+  });
+
+  return "{" + join(std::move(json), ", ") + "}";
+}
+//! [Struct]
+
+//! [Sequence]
+template <typename Xs>
+  std::enable_if_t<hana::Sequence<Xs>::value,
+std::string> to_json(Xs const& xs) {
+  auto json = hana::transform(xs, [](auto const& x) {
+    return to_json(x);
+  });
+
+  return "[" + join(std::move(json), ", ") + "]";
+}
+//! [Sequence]
+
+
+int main() {
+//! [usage]
+struct Car {
+  BOOST_HANA_DEFINE_STRUCT(Car,
+    (std::string, brand),
+    (std::string, model)
+  );
+};
+
+struct Person {
+  BOOST_HANA_DEFINE_STRUCT(Person,
+    (std::string, name),
+    (std::string, last_name),
+    (int, age)
+  );
+};
+
+Car bmw{"BMW", "Z3"}, audi{"Audi", "A4"};
+Person john{"John", "Doe", 30};
+
+auto tuple = hana::make_tuple(john, audi, bmw);
+std::cout << to_json(tuple) << std::endl;
+//! [usage]
+}