Migrate std::bind calls to lambda expressions (#659)

* ♻️ Actions tutorial lambda refactor

Signed-off-by: Felipe Gomes de Melo <[email protected]>

* ♻️ Composition nodes lambda refactor

Signed-off-by: Felipe Gomes de Melo <[email protected]>

* ♻️ Lifecycle nodes lambda refactor

Signed-off-by: Felipe Gomes de Melo <[email protected]>

* ♻️ Logging demo lambda refactor

Signed-off-by: Felipe Gomes de Melo <[email protected]>

* ♻️ Image tools lambda refactor

Signed-off-by: Felipe Gomes de Melo <[email protected]>

* ♻️  Intra process lambda refactor

Signed-off-by: Felipe Gomes de Melo <[email protected]>

* 🎨 Format code

Signed-off-by: Felipe Gomes de Melo <[email protected]>

---------

Signed-off-by: Felipe Gomes de Melo <[email protected]>

Author: FelipeGdM

action_tutorials/action_tutorials_cpp/README.md

@@ -4,16 +4,17 @@ In the constructor for `FibonacciActionServer`, an action server is created with
 
 ```cpp
 this->action_server_ = rclcpp_action::create_server<Fibonacci>(
-  ...
+  this,
   "fibonacci",
-  std::bind(&FibonacciActionServer::handle_goal, this, _1, _2),
-  std::bind(&FibonacciActionServer::handle_cancel, this, _1),
-  std::bind(&FibonacciActionServer::handle_accepted, this, _1));
+  handle_goal,
+  handle_cancel,
+  handle_accepted);
 ```
 
 The `handle_goal` callback is called whenever a goal is sent to the action server by an action client.
 In the example code, the goal is accepted as long as the order is less than or equal to 46, otherwise it is rejected.
 This is to prevent potential [integer overflow](https://en.wikipedia.org/wiki/Integer_overflow):
+
 ```cpp
 if (goal->order > 46) {
   return rclcpp_action::GoalResponse::REJECT;
@@ -25,8 +26,10 @@ The `handle_cancelled` callback is called whenever an action client requests to
 In this case, the goal cancel request is always accepted.
 
 The `handle_accepted` callback is called following the action server's acceptance of a goal. In this example, a thread is started to execute the goal:
+
 ```cpp
-std::thread{std::bind(&FibonacciActionServer::execute, this, _1), goal_handle}.detach();
+auto execute_in_thread = [this, goal_handle](){return this->execute(goal_handle);};
+std::thread{execute_in_thread}.detach();
 ```
 
 The execution thread calculates the Fibonacci sequence up to *order* and publishes partial sequences as feedback as each item is added to the sequence.
@@ -51,12 +54,16 @@ The goal is sent asynchronously with callbacks registered for the goal response,
 
 ```cpp
 auto send_goal_options = rclcpp_action::Client<Fibonacci>::SendGoalOptions();
-send_goal_options.goal_response_callback =
-  std::bind(&FibonacciActionClient::goal_response_callback, this, _1);
-send_goal_options.feedback_callback =
-  std::bind(&FibonacciActionClient::feedback_callback, this, _1, _2);
-send_goal_options.result_callback =
-  std::bind(&FibonacciActionClient::result_callback, this, _1);
+send_goal_options.goal_response_callback = [this](
+  const GoalHandleFibonacci::SharedPtr & goal_handle)
+{...};
+send_goal_options.feedback_callback = [this](
+  GoalHandleFibonacci::SharedPtr,
+  const std::shared_ptr<const Fibonacci::Feedback> feedback)
+{...};
+send_goal_options.result_callback = [this](
+  const GoalHandleFibonacci::WrappedResult & result)
+{...};
 this->client_ptr_->async_send_goal(goal_msg, send_goal_options);
 ```
 

action_tutorials/action_tutorials_cpp/src/fibonacci_action_client.cpp

@@ -45,7 +45,7 @@ class FibonacciActionClient : public rclcpp::Node
 
     this->timer_ = this->create_wall_timer(
       std::chrono::milliseconds(500),
-      std::bind(&FibonacciActionClient::send_goal, this));
+      [this]() {return this->send_goal();});
   }
 
   ACTION_TUTORIALS_CPP_PUBLIC
@@ -67,67 +67,59 @@ class FibonacciActionClient : public rclcpp::Node
     RCLCPP_INFO(this->get_logger(), "Sending goal");
 
     auto send_goal_options = rclcpp_action::Client<Fibonacci>::SendGoalOptions();
-    send_goal_options.goal_response_callback =
-      std::bind(&FibonacciActionClient::goal_response_callback, this, _1);
-    send_goal_options.feedback_callback =
-      std::bind(&FibonacciActionClient::feedback_callback, this, _1, _2);
-    send_goal_options.result_callback =
-      std::bind(&FibonacciActionClient::result_callback, this, _1);
+    send_goal_options.goal_response_callback = [this](
+      const GoalHandleFibonacci::SharedPtr & goal_handle)
+      {
+        if (!goal_handle) {
+          RCLCPP_ERROR(this->get_logger(), "Goal was rejected by server");
+        } else {
+          RCLCPP_INFO(this->get_logger(), "Goal accepted by server, waiting for result");
+        }
+      };
+
+    send_goal_options.feedback_callback = [this](
+      GoalHandleFibonacci::SharedPtr,
+      const std::shared_ptr<const Fibonacci::Feedback> feedback)
+      {
+        std::stringstream ss;
+        ss << "Next number in sequence received: ";
+        for (auto number : feedback->partial_sequence) {
+          ss << number << " ";
+        }
+        RCLCPP_INFO(this->get_logger(), ss.str().c_str());
+      };
+
+    send_goal_options.result_callback = [this](
+      const GoalHandleFibonacci::WrappedResult & result)
+      {
+        switch (result.code) {
+          case rclcpp_action::ResultCode::SUCCEEDED:
+            break;
+          case rclcpp_action::ResultCode::ABORTED:
+            RCLCPP_ERROR(this->get_logger(), "Goal was aborted");
+            return;
+          case rclcpp_action::ResultCode::CANCELED:
+            RCLCPP_ERROR(this->get_logger(), "Goal was canceled");
+            return;
+          default:
+            RCLCPP_ERROR(this->get_logger(), "Unknown result code");
+            return;
+        }
+        std::stringstream ss;
+        ss << "Result received: ";
+        for (auto number : result.result->sequence) {
+          ss << number << " ";
+        }
+        RCLCPP_INFO(this->get_logger(), ss.str().c_str());
+        rclcpp::shutdown();
+      };
+
     this->client_ptr_->async_send_goal(goal_msg, send_goal_options);
   }
 
 private:
   rclcpp_action::Client<Fibonacci>::SharedPtr client_ptr_;
   rclcpp::TimerBase::SharedPtr timer_;
-
-  ACTION_TUTORIALS_CPP_LOCAL
-  void goal_response_callback(GoalHandleFibonacci::SharedPtr goal_handle)
-  {
-    if (!goal_handle) {
-      RCLCPP_ERROR(this->get_logger(), "Goal was rejected by server");
-      rclcpp::shutdown();
-    } else {
-      RCLCPP_INFO(this->get_logger(), "Goal accepted by server, waiting for result");
-    }
-  }
-
-  ACTION_TUTORIALS_CPP_LOCAL
-  void feedback_callback(
-    GoalHandleFibonacci::SharedPtr,
-    const std::shared_ptr<const Fibonacci::Feedback> feedback)
-  {
-    std::stringstream ss;
-    ss << "Next number in sequence received: ";
-    for (auto number : feedback->partial_sequence) {
-      ss << number << " ";
-    }
-    RCLCPP_INFO(this->get_logger(), "%s", ss.str().c_str());
-  }
-
-  ACTION_TUTORIALS_CPP_LOCAL
-  void result_callback(const GoalHandleFibonacci::WrappedResult & result)
-  {
-    switch (result.code) {
-      case rclcpp_action::ResultCode::SUCCEEDED:
-        break;
-      case rclcpp_action::ResultCode::ABORTED:
-        RCLCPP_ERROR(this->get_logger(), "Goal was aborted");
-        return;
-      case rclcpp_action::ResultCode::CANCELED:
-        RCLCPP_ERROR(this->get_logger(), "Goal was canceled");
-        return;
-      default:
-        RCLCPP_ERROR(this->get_logger(), "Unknown result code");
-        return;
-    }
-    std::stringstream ss;
-    ss << "Result received: ";
-    for (auto number : result.result->sequence) {
-      ss << number << " ";
-    }
-    RCLCPP_INFO(this->get_logger(), "%s", ss.str().c_str());
-    rclcpp::shutdown();
-  }
 };  // class FibonacciActionClient
 
 }  // namespace action_tutorials_cpp

action_tutorials/action_tutorials_cpp/src/fibonacci_action_server.cpp

@@ -36,53 +36,49 @@ class FibonacciActionServer : public rclcpp::Node
   {
     using namespace std::placeholders;
 
+    auto handle_goal = [this](
+      const rclcpp_action::GoalUUID & uuid,
+      std::shared_ptr<const Fibonacci::Goal> goal)
+      {
+        (void)uuid;
+        RCLCPP_INFO(this->get_logger(), "Received goal request with order %d", goal->order);
+        // The Fibonacci action uses int32 for the return of sequences, which means it can only hold
+        // 2^31-1 (2147483647) before wrapping negative in two's complement. Based on empirical
+        // tests, that means that an order of > 46 will cause wrapping, so we don't allow that here.
+        if (goal->order > 46) {
+          return rclcpp_action::GoalResponse::REJECT;
+        }
+        return rclcpp_action::GoalResponse::ACCEPT_AND_EXECUTE;
+      };
+
+    auto handle_cancel = [this](
+      const std::shared_ptr<GoalHandleFibonacci> goal_handle)
+      {
+        RCLCPP_INFO(this->get_logger(), "Received request to cancel goal");
+        (void)goal_handle;
+        return rclcpp_action::CancelResponse::ACCEPT;
+      };
+
+    auto handle_accepted = [this](
+      const std::shared_ptr<GoalHandleFibonacci> goal_handle)
+      {
+        // this needs to return quickly to avoid blocking the executor,
+        // so we declare a lambda function to be called inside a new thread
+        auto execute_in_thread = [this, goal_handle]() {return this->execute(goal_handle);};
+        std::thread{execute_in_thread}.detach();
+      };
+
     this->action_server_ = rclcpp_action::create_server<Fibonacci>(
-      this->get_node_base_interface(),
-      this->get_node_clock_interface(),
-      this->get_node_logging_interface(),
-      this->get_node_waitables_interface(),
+      this,
       "fibonacci",
-      std::bind(&FibonacciActionServer::handle_goal, this, _1, _2),
-      std::bind(&FibonacciActionServer::handle_cancel, this, _1),
-      std::bind(&FibonacciActionServer::handle_accepted, this, _1));
+      handle_goal,
+      handle_cancel,
+      handle_accepted);
   }
 
 private:
   rclcpp_action::Server<Fibonacci>::SharedPtr action_server_;
 
-  ACTION_TUTORIALS_CPP_LOCAL
-  rclcpp_action::GoalResponse handle_goal(
-    const rclcpp_action::GoalUUID & uuid,
-    std::shared_ptr<const Fibonacci::Goal> goal)
-  {
-    (void)uuid;
-    RCLCPP_INFO(this->get_logger(), "Received goal request with order %d", goal->order);
-    // The Fibonacci action uses int32 for the return of sequences, which means it can only
-    // hold 2^31-1 (2147483647) before wrapping negative in two's complement.  Based on empirical
-    // tests, that means that an order of > 46 will cause wrapping, so we don't allow that here.
-    if (goal->order > 46) {
-      return rclcpp_action::GoalResponse::REJECT;
-    }
-    return rclcpp_action::GoalResponse::ACCEPT_AND_EXECUTE;
-  }
-
-  ACTION_TUTORIALS_CPP_LOCAL
-  rclcpp_action::CancelResponse handle_cancel(
-    const std::shared_ptr<GoalHandleFibonacci> goal_handle)
-  {
-    RCLCPP_INFO(this->get_logger(), "Received request to cancel goal");
-    (void)goal_handle;
-    return rclcpp_action::CancelResponse::ACCEPT;
-  }
-
-  ACTION_TUTORIALS_CPP_LOCAL
-  void handle_accepted(const std::shared_ptr<GoalHandleFibonacci> goal_handle)
-  {
-    using namespace std::placeholders;
-    // this needs to return quickly to avoid blocking the executor, so spin up a new thread
-    std::thread{std::bind(&FibonacciActionServer::execute, this, _1), goal_handle}.detach();
-  }
-
   ACTION_TUTORIALS_CPP_LOCAL
   void execute(const std::shared_ptr<GoalHandleFibonacci> goal_handle)
   {

composition/src/client_component.cpp

@@ -33,7 +33,7 @@ Client::Client(const rclcpp::NodeOptions & options)
   // Note(dhood): The timer period must be greater than the duration of the timer callback.
   // Otherwise, the timer can starve a single-threaded executor.
   // See https://github.com/ros2/rclcpp/issues/392 for updates.
-  timer_ = create_wall_timer(2s, std::bind(&Client::on_timer, this));
+  timer_ = create_wall_timer(2s, [this]() {return this->on_timer();});
 }
 
 void Client::on_timer()

composition/src/talker_component.cpp

@@ -37,7 +37,7 @@ Talker::Talker(const rclcpp::NodeOptions & options)
   pub_ = create_publisher<std_msgs::msg::String>("chatter", 10);
 
   // Use a timer to schedule periodic message publishing.
-  timer_ = create_wall_timer(1s, std::bind(&Talker::on_timer, this));
+  timer_ = create_wall_timer(1s, [this]() {return this->on_timer();});
 }
 
 void Talker::on_timer()

image_tools/src/cam2image.cpp

@@ -110,7 +110,7 @@ class Cam2Image : public rclcpp::Node
     // Start main timer loop
     timer_ = this->create_wall_timer(
       std::chrono::milliseconds(static_cast<int>(1000.0 / freq_)),
-      std::bind(&Cam2Image::timerCallback, this));
+      [this]() {return this->timerCallback();});
   }
 
   /// Publish camera, or burger, image.

intra_process_demo/include/image_pipeline/camera_node.hpp

@@ -61,7 +61,7 @@ class CameraNode final : public rclcpp::Node
     // Create a publisher on the output topic.
     pub_ = this->create_publisher<sensor_msgs::msg::Image>(output, rclcpp::SensorDataQoS());
     // Create the camera reading loop.
-    thread_ = std::thread(std::bind(&CameraNode::loop, this));
+    thread_ = std::thread([this]() {return this->loop();});
   }
 
   ~CameraNode()

lifecycle/src/lifecycle_listener.cpp

@@ -39,15 +39,18 @@ class LifecycleListener : public rclcpp::Node
     // Data topic from the lc_talker node
     sub_data_ = this->create_subscription<std_msgs::msg::String>(
       "lifecycle_chatter", 10,
-      std::bind(&LifecycleListener::data_callback, this, std::placeholders::_1));
+      [this](std_msgs::msg::String::ConstSharedPtr msg) {return this->data_callback(msg);});
 
     // Notification event topic. All state changes
     // are published here as TransitionEvents with
     // a start and goal state indicating the transition
     sub_notification_ = this->create_subscription<lifecycle_msgs::msg::TransitionEvent>(
       "/lc_talker/transition_event",
       10,
-      std::bind(&LifecycleListener::notification_callback, this, std::placeholders::_1));
+      [this](lifecycle_msgs::msg::TransitionEvent::ConstSharedPtr msg) {
+        return this->notification_callback(msg);
+      }
+    );
   }
 
   void data_callback(std_msgs::msg::String::ConstSharedPtr msg)

lifecycle/src/lifecycle_service_client.cpp

@@ -328,10 +328,16 @@ int main(int argc, char ** argv)
 
   std::shared_future<void> script = std::async(
     std::launch::async,
-    std::bind(callee_script, lc_client));
+    callee_script,
+    lc_client
+  );
+
   auto wake_exec = std::async(
     std::launch::async,
-    std::bind(wake_executor, script, std::ref(exe)));
+    wake_executor,
+    script,
+    std::ref(exe)
+  );
 
   exe.spin_until_future_complete(script);
 

lifecycle/src/lifecycle_talker.cpp

@@ -116,7 +116,7 @@ class LifecycleTalker : public rclcpp_lifecycle::LifecycleNode
     // available.
     pub_ = this->create_publisher<std_msgs::msg::String>("lifecycle_chatter", 10);
     timer_ = this->create_wall_timer(
-      1s, std::bind(&LifecycleTalker::publish, this));
+      1s, [this]() {return this->publish();});
 
     RCLCPP_INFO(get_logger(), "on_configure() is called.");