state.h File Reference

This file contains the definition of the state class and related helper templates. More...

#include <optional>
#include <type_traits>
#include "../base/type_traits.h"
#include "transition.h"

Include dependency graph for state.h:

This graph shows which files directly or indirectly include this file:

Go to the source code of this file.

Classes
struct	escad::new_fsm::detail::NoContext
struct	escad::new_fsm::detail::InternalEvent
struct	escad::new_fsm::detail::has_onEnter< Target, typename >
	Default case of helper for detecting if type Target has a onEnter() method. More...
struct	escad::new_fsm::detail::has_onEnter< Target, std::void_t< decltype(std::declval< Target >().onEnter())> >
	Specialization for detecting if type Target has a onEnter() method. More...
struct	escad::new_fsm::detail::has_onEnterWithEvent< Target, Event, typename >
	Default case of helper for detecting if type Target has a onEnter(const Event &) method. More...
struct	escad::new_fsm::detail::has_onEnterWithEvent< Target, Event, std::void_t< decltype(std::declval< Target >().onEnter(std::declval< Event >()))> >
	Specialization for detecting if type Target has a onEnter(const Event &) method. More...
struct	escad::new_fsm::detail::has_onExit< Target, typename >
struct	escad::new_fsm::detail::has_onExit< Target, std::void_t< decltype(std::declval< Target >().onExit())> >
struct	escad::new_fsm::detail::has_transitionTo< Target, Event, typename >
	Default case of helper for detecting if type Target has a transitionTo(const Event &) method. More...
struct	escad::new_fsm::detail::has_transitionTo< Target, Event, std::void_t< decltype(std::declval< Target >().transitionTo(std::declval< Event >()))> >
	Specialization for detecting if type Target has a transitionTo(const Event &) method. More...
struct	escad::new_fsm::detail::has_transitionInternalTo< Target, typename >
struct	escad::new_fsm::detail::has_transitionInternalTo< Target, std::void_t< decltype(std::declval< Target >().transitionInternalTo())> >
struct	escad::new_fsm::states< S >
	Defines a set of states. More...
struct	escad::new_fsm::state< Derived, Context >
	state is a CRTP base class for states. More...

Variables
template<class T >
constexpr bool	escad::new_fsm::detail::has_onEnter_v = has_onEnter<T>::value
	Helper helper template to access the value of has_onEnter. More...
template<class T , class E >
constexpr bool	escad::new_fsm::detail::has_onEnterWithEvent_v
	Helper helper template to access the value of has_onEnterWithEvent. More...
template<class T >
constexpr bool	escad::new_fsm::detail::has_onExit_v = has_onExit<T>::value
template<class T , class E >
constexpr bool	escad::new_fsm::detail::has_transitionTo_v = has_transitionTo<T, E>::value
	Helper helper template to access the value of has_transitionTo. More...
template<class T >
constexpr bool	escad::new_fsm::detail::has_transitionInternalTo_v

Detailed Description

This file contains the definition of the state class and related helper templates.

Defines the state class and helper templates for state management in a finite state machine.

The state class is a CRTP (Curiously Recurring Template Pattern) base class for states in a finite state machine. It provides methods for handling state entry, event dispatching, and state transitions. The helper templates in this file are used for detecting if a state has specific methods, such as onEnter() and transitionTo(). This file is part of the FSM (Finite State Machine) library.

Author

Martin Heubuch (marti.nosp@m.n.he.nosp@m.ubuch.nosp@m.@esc.nosp@m.ad.de)

Version

0.1

Date

2023-02-23

This file contains the implementation of the state class, which is a CRTP (Curiously Recurring Template Pattern) base class for states in a finite state machine. It also includes helper templates for detecting the presence of certain methods in derived state classes.

The state class provides methods for handling state entry, event dispatching, and state transitions. It uses SFINAE (Substitution Failure Is Not An Error) and type traits to conditionally call methods based on their existence in the derived state class.

The helper templates in the details namespace are used to detect the presence of the following methods in the derived state class:

• onEnter(): Called when entering the state without an event.
• onEnter(const Event&): Called when entering the state with an event.
• transitionTo(const Event&): Called to transition to another state based on an event.

The state class also includes a handle_result() method for handling the result of state transitions and a dispatch() method for dispatching events to the state.

This file is part of the new_fsm namespace.

Variable Documentation

has_onEnter_v

template<class T >

constexpr bool escad::new_fsm::detail::has_onEnter_v = has_onEnter<T>::value

inline

Helper helper template to access the value of has_onEnter.

Template Parameters

T	The type to check for the presence of onEnter() method.

has_onEnterWithEvent_v

template<class T , class E >

constexpr bool escad::new_fsm::detail::has_onEnterWithEvent_v

inline

Initial value:

=
    has_onEnterWithEvent<T, E>::value

Helper helper template to access the value of has_onEnterWithEvent.

Template Parameters

T	The type to check for the presence of onEnter(const Event &) method.
E	The event type.

has_transitionInternalTo_v

template<class T >

constexpr bool escad::new_fsm::detail::has_transitionInternalTo_v

inline

Initial value:

=
    has_transitionInternalTo<T>::value

has_transitionTo_v

template<class T , class E >

constexpr bool escad::new_fsm::detail::has_transitionTo_v = has_transitionTo<T, E>::value

inline

Helper helper template to access the value of has_transitionTo.

Template Parameters

T	The type to check for the presence of transitionTo(const Event &) method.
E	The event type.