Support conversion between vector<Any> and vector<typename T::value_type>

include/behaviortree_cpp/basic_types.h

@@ -375,7 +375,8 @@ class TypeInfo
 
  [[nodiscard]] bool isStronglyTyped() const
  {
- return type_info_ != typeid(AnyTypeAllowed) && type_info_ != typeid(BT::Any);
+ return type_info_ != typeid(AnyTypeAllowed) && type_info_ != typeid(BT::Any) &&
+ type_info_ != typeid(std::vector<BT::Any>);
  }
 
  [[nodiscard]] const StringConverter& converter() const

include/behaviortree_cpp/blackboard.h

@@ -257,8 +257,13 @@ inline void Blackboard::set(const std::string& key, const T& value)
 
  std::type_index previous_type = entry.info.type();
 
+ // Allow mismatch if going from vector -> vector<Any>.
+ bool previous_is_vector = std::string(previous_type.name()).find("vector") != std::string::npos;
+ bool new_is_vector_any = new_value.type() == typeid(std::vector<Any>);
+
  // check type mismatch
- if(previous_type != std::type_index(typeid(T)) && previous_type != new_value.type())
+ if(previous_type != std::type_index(typeid(T)) && previous_type != new_value.type() &&
+ !(previous_is_vector && new_is_vector_any))
  {
  bool mismatching = true;
  if(std::is_constructible<StringView, T>::value)

include/behaviortree_cpp/tree_node.h

@@ -30,6 +30,12 @@
 
 namespace BT
 {
+// Helper trait to check if a type is a std::vector
+template <typename T>
+struct is_vector : std::false_type {};
+
+template <typename T, typename A>
+struct is_vector<std::vector<T, A>> : std::true_type {};
 
 /// This information is used mostly by the XMLParser.
 struct TreeNodeManifest
@@ -521,6 +527,26 @@ inline Expected<Timestamp> TreeNode::getInputStamped(const std::string& key,
 
  if(!entry->value.empty())
  {
+ // Support vector<Any> -> vector<typename T::value_type> conversion.
+ // Only want to compile this path when T is a vector type.
+ if constexpr (is_vector<T>::value)
+ {
+ if (!std::is_same_v<T, std::vector<Any>> && any_value.type() == typeid(std::vector<Any>))
+ {
+ // If the object was originally placed on the blackboard as a vector<Any>, attempt to unwrap the vector
+ // elements according to the templated type.
+ auto any_vec = any_value.cast<std::vector<Any>>();
+ if (!any_vec.empty() && any_vec.front().type() != typeid(typename T::value_type))
+ {
+ return nonstd::make_unexpected("Invalid cast requested from vector<Any> to vector<typename T::value_type>."
+ " Element type does not align.");
+ }
+ destination = T();
+ std::transform(any_vec.begin(), any_vec.end(), std::back_inserter(destination),
+ [](Any &element) { return element.cast<typename T::value_type>(); });
+ return Timestamp{ entry->sequence_id, entry->stamp };
+ }
+ }
  if(!std::is_same_v<T, std::string> && any_value.isString())
  {
  destination = parseString<T>(any_value.cast<std::string>());
@@ -593,7 +619,19 @@ inline Result TreeNode::setOutput(const std::string& key, const T& value)
  }
 
  remapped_key = stripBlackboardPointer(remapped_key);
- config().blackboard->set(static_cast<std::string>(remapped_key), value);
+
+ if constexpr(is_vector<T>::value && !std::is_same_v<T, std::vector<Any>>)
+ {
+ // If the object is a vector but not a vector<Any>, convert it to vector<Any> before placing it on the blackboard.
+ auto any_vec = std::vector<Any>();
+ std::transform(value.begin(), value.end(), std::back_inserter(any_vec),
+ [](const auto &element) { return BT::Any(element); });
+ config().blackboard->set(static_cast<std::string>(remapped_key), any_vec);
+ }
+ else
+ {
+ config().blackboard->set(static_cast<std::string>(remapped_key), value);
+ }
 
  return {};
 }

src/xml_parsing.cpp

@@ -786,8 +786,14 @@ TreeNode::Ptr XMLParser::PImpl::createNodeFromXML(const XMLElement* element,
 
  // special case related to convertFromString
  bool const string_input = (prev_info->type() == typeid(std::string));
-
- if(port_type_mismatch && !string_input)
+ // special case related to unwrapping vector<Any> -> vector<T> objects.
+ bool const vec_any_input = (prev_info->type() == typeid(std::vector<Any>));
+ // special case related to wrapping vector<T> -> vector<Any> objects.
+ bool previous_is_vector = std::string(prev_info->type().name()).find("vector") != std::string::npos;
+ bool new_is_vector_any = port_info.type() == typeid(std::vector<Any>);
+
+ if(port_type_mismatch && !string_input &&
+ !vec_any_input & !(previous_is_vector && new_is_vector_any))
  {
  blackboard->debugMessage();