yasmin.state.State Class Reference

Inheritance diagram for yasmin.state.State:

Collaboration diagram for yasmin.state.State:

Public Member Functions
None	__init__ (self, Set[str] outcomes)
str	__call__ (self, Blackboard blackboard=None)
str	execute (self, Blackboard blackboard)
str	__str__ (self)
None	cancel_state (self)
bool	is_canceled (self)
bool	is_running (self)
Set[str]	get_outcomes (self)

Protected Attributes
Set	_outcomes = set()
	A set of valid outcomes for this state.
bool	_running = False
	A flag indicating whether the state is currently running.
bool	_canceled = False
	A flag indicating whether the state has been canceled.

Detailed Description

Abstract base class representing a state in a state machine.

This class provides a framework for creating specific states with defined outcomes.
Subclasses must implement the `execute` method to define the state-specific behavior.

Attributes:
    _outcomes (Set[str]): A set of valid outcomes for this state.
    _running (bool): A flag indicating whether the state is currently running.
    _canceled (bool): A flag indicating whether the state has been canceled.

Constructor & Destructor Documentation

__init__()

None yasmin.state.State.__init__	(		self,
		Set[str]	outcomes )

Initializes the State instance.

:param outcomes: A set of valid outcomes for this state.
                 Must contain at least one outcome.
:raises ValueError: If the provided outcomes set is empty.

Reimplemented in yasmin.cb_state.CbState, yasmin.state_machine.StateMachine, yasmin_demos.action_client_demo.FibonacciState, yasmin_demos.monitor_demo.PrintOdometryState, yasmin_demos.nav_demo.Nav2State, yasmin_demos.service_client_demo.AddTwoIntsState, yasmin_demos.yasmin_demo.BarState, yasmin_demos.yasmin_demo.FooState, yasmin_ros.action_state.ActionState, yasmin_ros.monitor_state.MonitorState, and yasmin_ros.service_state.ServiceState.

Member Function Documentation

__call__()

str yasmin.state.State.__call__	(		self,
		Blackboard	blackboard = None )

Executes the state and returns the outcome.

This method sets the state as running, executes the state's behavior,
and validates the outcome against the allowed outcomes.

:param blackboard: An optional Blackboard instance that can be used during execution.
                   If None, a new Blackboard instance will be created.
:return: The outcome of the state execution.
:raises ValueError: If the outcome is not one of the valid outcomes for this state.

__str__()

str yasmin.state.State.__str__

(

self

)

Returns the string representation of the state.

:return: The name of the class representing the state.

Reimplemented in yasmin.state_machine.StateMachine.

cancel_state()

None yasmin.state.State.cancel_state

(

self

)

Cancels the execution of the state.

Sets the _canceled flag to True and logs the cancellation.

Reimplemented in yasmin.state_machine.StateMachine, and yasmin_ros.action_state.ActionState.

execute()

str yasmin.state.State.execute	(		self,
		Blackboard	blackboard )

Executes the specific behavior of the state.

This method must be implemented by subclasses to define what happens
when the state is executed.

:param blackboard: An instance of Blackboard that provides the context for execution.
:return: The outcome of the execution as a string.
:raises NotImplementedError: If not implemented in a subclass.

Reimplemented in yasmin.cb_state.CbState, yasmin.state_machine.StateMachine, yasmin_demos.yasmin_demo.BarState, yasmin_demos.yasmin_demo.FooState, yasmin_ros.action_state.ActionState, yasmin_ros.monitor_state.MonitorState, and yasmin_ros.service_state.ServiceState.

get_outcomes()

Set[str] yasmin.state.State.get_outcomes

(

self

)

Gets the valid outcomes for this state.

:return: A set of valid outcomes as strings.

is_canceled()

bool yasmin.state.State.is_canceled

(

self

)

Checks if the state has been canceled.

:return: True if the state is canceled, False otherwise.

is_running()

bool yasmin.state.State.is_running

(

self

)

Checks if the state is currently running.

:return: True if the state is running, False otherwise.

Member Data Documentation

_canceled

bool yasmin.state.State._canceled = False

protected

A flag indicating whether the state has been canceled.

_outcomes

Set yasmin.state.State._outcomes = set()

protected

A set of valid outcomes for this state.

_running

bool yasmin.state.State._running = False

protected

A flag indicating whether the state is currently running.

---

The documentation for this class was generated from the following file:

• yasmin/yasmin/state.py