Class BlackboardPyWrapper

Class Documentation

class BlackboardPyWrapper

Python-facing wrapper around the native Blackboard.

The underlying Blackboard stores strongly typed C++ values. This wrapper translates common Python types into matching C++ types on write and converts them back into Python objects on read.

Supported scalar mappings:

  • bool <-> bool

  • int <-> std::int64_t

  • float <-> double

  • str <-> std::string

  • bytes / bytearray <-> std::vector<uint8_t>

Supported homogeneous container mappings:

  • list[str] / tuple[str, …] <-> std::vector<std::string>

  • list[int] / tuple[int, …] <-> std::vector<std::int64_t>

  • list[float] / tuple[float, …] <-> std::vector<double>

  • list[bool] / tuple[bool, …] <-> std::vector<bool>

  • dict[str, str] <-> std::unordered_map<std::string, std::string>

  • dict[str, int] <-> std::unordered_map<std::string, std::int64_t>

  • dict[str, float] <-> std::unordered_map<std::string, double>

  • dict[str, bool] <-> std::unordered_map<std::string, bool>

Mixed containers, nested containers, and empty containers are stored as py::object because no unique native C++ element type can be inferred safely.

Public Functions

inline BlackboardPyWrapper()

Construct a wrapper with a newly created native Blackboard.

inline BlackboardPyWrapper(Blackboard &&other)

Construct a wrapper by moving an existing native Blackboard.

Parameters:

other – Native blackboard instance to move into shared ownership.

inline explicit BlackboardPyWrapper(Blackboard::SharedPtr bb_ptr)

Construct a wrapper from an existing shared native Blackboard.

Parameters:

bb_ptr – Shared pointer to a native Blackboard.

inline void set(const std::string &key, py::object value)

Store a Python object in the blackboard.

The wrapper first tries to map the value to a native C++ type. If no safe native mapping exists, the value is stored as py::object.

Parameters:

  • key – Blackboard key.

  • value – Python object to store.

inline py::object get(const std::string &key) const

Retrieve a Python object from the blackboard.

The native blackboard stores the type name of each entry. This method uses that exact stored type information to select the matching conversion path.

Parameters:

key – Blackboard key.

Returns:

Python object reconstructed from the stored native value.

inline void remove(const std::string &key)

Remove a value from the blackboard.

Parameters:

key – Blackboard key to remove.

inline bool contains(const std::string &key) const

Check whether a key exists in the blackboard.

Parameters:

key – Blackboard key to test.

Returns:

True if the key exists.

inline int size() const

Get the number of entries in the blackboard.

Returns:

Number of stored key-value pairs.

inline std::string to_string() const

Get a string representation of the blackboard contents.

Returns:

Human-readable description of the stored keys and types.

inline void set_remappings(const Remappings &remappings)

Set key remappings on the underlying blackboard.

Parameters:

remappings – Remapping table to apply.

inline const Remappings &get_remappings() const

Get the current key remappings.

Returns:

Reference to the underlying remapping table.

inline Blackboard::SharedPtr get_cpp_blackboard() const

Access the underlying native blackboard.

Returns:

Shared pointer to the native blackboard instance.