Migrate remaining c++03 examples to c++11.

example/cpp11/tutorial/timer5/timer.cpp

@@ -0,0 +1,81 @@
+//
+// timer.cpp
+// ~~~~~~~~~
+//
+// Copyright (c) 2003-2023 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// 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)
+//
+
+#include <functional>
+#include <iostream>
+#include <thread>
+#include <boost/asio.hpp>
+
+class printer
+{
+public:
+  printer(boost::asio::io_context& io)
+    : strand_(boost::asio::make_strand(io)),
+      timer1_(io, boost::asio::chrono::seconds(1)),
+      timer2_(io, boost::asio::chrono::seconds(1)),
+      count_(0)
+  {
+    timer1_.async_wait(boost::asio::bind_executor(strand_,
+          std::bind(&printer::print1, this)));
+
+    timer2_.async_wait(boost::asio::bind_executor(strand_,
+          std::bind(&printer::print2, this)));
+  }
+
+  ~printer()
+  {
+    std::cout << "Final count is " << count_ << std::endl;
+  }
+
+  void print1()
+  {
+    if (count_ < 10)
+    {
+      std::cout << "Timer 1: " << count_ << std::endl;
+      ++count_;
+
+      timer1_.expires_at(timer1_.expiry() + boost::asio::chrono::seconds(1));
+
+      timer1_.async_wait(boost::asio::bind_executor(strand_,
+            std::bind(&printer::print1, this)));
+    }
+  }
+
+  void print2()
+  {
+    if (count_ < 10)
+    {
+      std::cout << "Timer 2: " << count_ << std::endl;
+      ++count_;
+
+      timer2_.expires_at(timer2_.expiry() + boost::asio::chrono::seconds(1));
+
+      timer2_.async_wait(boost::asio::bind_executor(strand_,
+            std::bind(&printer::print2, this)));
+    }
+  }
+
+private:
+  boost::asio::strand<boost::asio::io_context::executor_type> strand_;
+  boost::asio::steady_timer timer1_;
+  boost::asio::steady_timer timer2_;
+  int count_;
+};
+
+int main()
+{
+  boost::asio::io_context io;
+  printer p(io);
+  std::thread t([&]{ io.run(); });
+  io.run();
+  t.join();
+
+  return 0;
+}