Added thirdparty: boost library

thirdparty/include/boost/cobalt/generator.hpp

@@ -0,0 +1,113 @@
+//
+// Copyright (c) 2022 Klemens Morgenstern (klemens.morgenstern@gmx.net)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_COBALT_GENERATOR_HPP
+#define BOOST_COBALT_GENERATOR_HPP
+
+#include <boost/cobalt/detail/generator.hpp>
+
+
+namespace boost::cobalt
+{
+
+// tag::outline[]
+template<typename Yield, typename Push = void>
+struct [[nodiscard]] generator
+// end::outline[]
+     : detail::generator_base<Yield, Push>
+// tag::outline[]
+{
+  // Movable
+
+  generator(generator &&lhs) noexcept = default;
+  generator& operator=(generator &&) noexcept = default;
+
+  // True until it co_returns & is co_awaited after <1>
+  explicit operator bool() const;
+
+  // Cancel the generator. <3>
+  void cancel(asio::cancellation_type ct = asio::cancellation_type::all);
+
+  // Check if a value is available
+  bool ready() const;
+
+  // Get the returned value. If !ready() this function has undefined behaviour.
+  Yield get();
+
+  // Cancel & detach the generator.
+  ~generator();
+
+  // end::outline[]
+  using promise_type = detail::generator_promise<Yield, Push>;
+
+  generator(const generator &) = delete;
+  generator& operator=(const generator &) = delete;
+
+
+ private:
+  template<typename, typename>
+  friend struct detail::generator_base;
+  template<typename, typename>
+  friend struct detail::generator_promise;
+
+  generator(detail::generator_promise<Yield, Push> * generator) : receiver_(generator->receiver, generator->signal)
+  {
+  }
+  detail::generator_receiver<Yield, Push> receiver_;
+
+  /* tag::outline[]
+  // an awaitable that results in value of `Yield`.
+  using __generator_awaitable__ = __unspecified__;
+
+  // Present when `Push` != `void`
+  __generator_awaitable__ operator()(      Push && push);
+  __generator_awaitable__ operator()(const Push &  push);
+
+  // Present when `Push` == `void`, i.e. can `co_await` the generator directly.
+  __generator_awaitable__ operator co_await (); // <2>
+   end::outline[]
+   */
+
+
+// tag::outline[]
+
+};
+// end::outline[]
+
+
+
+template<typename Yield, typename Push >
+inline generator<Yield, Push>::operator bool() const
+{
+  return !receiver_.done || receiver_.result || receiver_.exception;
+}
+
+template<typename Yield, typename Push >
+inline void generator<Yield, Push>::cancel(asio::cancellation_type ct)
+{
+  if (!receiver_.done && receiver_.reference == &receiver_)
+    receiver_.cancel_signal.emit(ct);
+}
+
+template<typename Yield, typename Push >
+inline bool generator<Yield, Push>::ready() const  { return receiver_.result || receiver_.exception; }
+
+template<typename Yield, typename Push >
+inline Yield generator<Yield, Push>::get()
+{
+  BOOST_ASSERT(ready());
+  receiver_.rethrow_if();
+  return receiver_.get_result();
+}
+
+template<typename Yield, typename Push >
+inline generator<Yield, Push>::~generator() { cancel(); }
+
+
+}
+
+#endif //BOOST_COBALT_GENERATOR_HPP