Improved the const-correctness of some actionlib classes.

include/actionlib/client/client_goal_handle_imp.h

@@ -89,7 +89,7 @@ bool ClientGoalHandle<ActionSpec>::isExpired() const
 
 
 template<class ActionSpec>
-CommState ClientGoalHandle<ActionSpec>::getCommState()
+CommState ClientGoalHandle<ActionSpec>::getCommState() const
 {
   if (!active_)
   {
@@ -111,7 +111,7 @@ CommState ClientGoalHandle<ActionSpec>::getCommState()
 }
 
 template<class ActionSpec>
-TerminalState ClientGoalHandle<ActionSpec>::getTerminalState()
+TerminalState ClientGoalHandle<ActionSpec>::getTerminalState() const
 {
 
   if (!active_)
@@ -158,7 +158,7 @@ TerminalState ClientGoalHandle<ActionSpec>::getTerminalState()
 }
 
 template<class ActionSpec>
-typename ClientGoalHandle<ActionSpec>::ResultConstPtr ClientGoalHandle<ActionSpec>::getResult()
+typename ClientGoalHandle<ActionSpec>::ResultConstPtr ClientGoalHandle<ActionSpec>::getResult() const
 {
   if (!active_)
     ROS_ERROR_NAMED("actionlib", "Trying to getResult on an inactive ClientGoalHandle. You are incorrectly using a ClientGoalHandle");

include/actionlib/client/client_helpers.h

@@ -155,7 +155,7 @@ class ClientGoalHandle
    *                      WAITING_FOR_CANCEL_ACK, RECALLING, PREEMPTING, DONE
    * \return The current goal's communication state with the server
    */
-  CommState getCommState();
+  CommState getCommState() const;
 
   /**
    * \brief Get the terminal state information for this goal
@@ -164,14 +164,14 @@ class ClientGoalHandle
    * This call only makes sense if CommState==DONE. This will send ROS_WARNs if we're not in DONE
    * \return The terminal state
    */
-  TerminalState getTerminalState();
+  TerminalState getTerminalState() const;
 
   /**
    * \brief Get result associated with this goal
    *
    * \return NULL if no reseult received.  Otherwise returns shared_ptr to result.
    */
-  ResultConstPtr getResult();
+  ResultConstPtr getResult() const;
 
   /**
    * \brief Resends this goal [with the same GoalID] to the ActionServer

include/actionlib/client/simple_action_client.h

@@ -38,6 +38,7 @@
 #include <boost/thread/condition.hpp>
 #include <boost/thread/mutex.hpp>
 #include <boost/scoped_ptr.hpp>
+#include <boost/concept_check.hpp>
 
 #include "ros/ros.h"
 #include "ros/callback_queue.h"
@@ -46,7 +47,6 @@
 #include "actionlib/client/simple_client_goal_state.h"
 #include "actionlib/client/terminal_state.h"
 
-
 #ifndef DEPRECATED
 #if defined(__GNUC__)
 #define DEPRECATED __attribute__((deprecated))
@@ -124,13 +124,16 @@ class SimpleActionClient
    * \param timeout Max time to block before returning. A zero timeout is interpreted as an infinite timeout.
    * \return True if the server connected in the allocated time. False on timeout
    */
-  bool waitForServer(const ros::Duration& timeout = ros::Duration(0,0) ) { return ac_->waitForActionServerToStart(timeout); }
+  bool waitForServer(const ros::Duration& timeout = ros::Duration(0,0) ) const
+  {
+    return ac_->waitForActionServerToStart(timeout);
+  }
 
   /**
    * @brief  Checks if the action client is successfully connected to the action server
    * @return True if the server is connected, false otherwise
    */
-  bool isServerConnected()
+  bool isServerConnected() const
   {
     return ac_->isServerConnected();
   }
@@ -175,15 +178,15 @@ class SimpleActionClient
    * \brief Get the Result of the current goal
    * \return shared pointer to the result. Note that this pointer will NEVER be NULL
    */
-  ResultConstPtr getResult();
+  ResultConstPtr getResult() const;
 
   /**
    * \brief Get the state information for this goal
    *
    * Possible States Are: PENDING, ACTIVE, RECALLED, REJECTED, PREEMPTED, ABORTED, SUCCEEDED, LOST.
    * \return The goal's state. Returns LOST if this SimpleActionClient isn't tracking a goal.
    */
-  SimpleClientGoalState getState();
+  SimpleClientGoalState getState() const;
 
   /**
    * \brief Cancel all goals currently running on the action server
@@ -331,7 +334,7 @@ void SimpleActionClient<ActionSpec>::sendGoal(const Goal& goal,
 }
 
 template<class ActionSpec>
-SimpleClientGoalState SimpleActionClient<ActionSpec>::getState()
+SimpleClientGoalState SimpleActionClient<ActionSpec>::getState() const
 {
   if (gh_.isExpired())
   {
@@ -395,7 +398,7 @@ SimpleClientGoalState SimpleActionClient<ActionSpec>::getState()
 }
 
 template<class ActionSpec>
-typename SimpleActionClient<ActionSpec>::ResultConstPtr SimpleActionClient<ActionSpec>::getResult()
+typename SimpleActionClient<ActionSpec>::ResultConstPtr SimpleActionClient<ActionSpec>::getResult() const
 {
   if (gh_.isExpired())
     ROS_ERROR_NAMED("actionlib", "Trying to getResult() when no goal is running. You are incorrectly using SimpleActionClient");

include/actionlib/managed_list.h

@@ -69,6 +69,8 @@ class ManagedList
       iterator() { }
       T& operator*()  { return it_->elem; }
       T& operator->() { return it_->elem; }
+      const T& operator*()  const { return it_->elem; }
+      const T& operator->() const { return it_->elem; }
       bool operator==(const iterator& rhs) const { return it_ == rhs.it_; }
       bool operator!=(const iterator& rhs) const { return !(*this == rhs); }
       void operator++() { it_++; }
@@ -154,6 +156,12 @@ class ManagedList
         assert(valid_);
         return *it_;
       }
+
+      const T& getElem() const
+      {
+        assert(valid_);
+        return *it_;
+      }
 
       /**
        * \brief Checks if two handles point to the same list elem