StateMachine

Defined in: state-machine.ts:26

StateMachine interface defines the contract for all state machine implementations in Matchina. It includes core lifecycle methods and hooks for managing state transitions, event handling, and side effects.

See also:

• FactoryMachine and createMachine for strongly-typed factory-based state machines.

Lifecycle steps:

1. send(type, ...params) - Initiates a transition event.
2. resolveExit(ev) - Determines the target state for the event.
3. transition(ev) - Triggers the transition lifecycle, handling all steps for processing a change event.
4. guard(ev) - Checks if the transition is allowed.
5. handle(ev) - Processes the event, may abort if returns undefined.
6. before(ev) - Prepares for state change, may abort if returns undefined.
7. update(ev) - Applies the state update.
8. effect(ev) - Runs side effects, calls leave/enter hooks.
9. leave(ev) - Called when leaving the previous state.
10. enter(ev) - Called when entering the new state.
11. notify(ev) - Notifies subscribers of the change.
12. after(ev) - Final hook after transition completes.

Extends

• EventLifecycle<E>

Type Parameters

Type Parameter	Default type
E extends TransitionEvent	TransitionEvent

Methods

transition()

transition(change: E): void

Defined in: event-lifecycle.ts:28

Triggers the transition lifecycle, handling all steps for processing a change event.

Parameters

Parameter	Type
change	E

Returns

void

Inherited from

EventLifecycle.transition

---

guard()

guard(ev: E): boolean

Defined in: event-lifecycle.ts:32

Checks if a transition event is allowed to proceed. Returns true to continue, false to abort.

Parameters

Parameter	Type
ev	E

Returns

boolean

Inherited from

EventLifecycle.guard

---

handle()

handle(ev: E): undefined | E

Defined in: event-lifecycle.ts:36

Processes the event. May abort the transition if returns undefined.

Parameters

Parameter	Type
ev	E

Returns

undefined | E

Inherited from

EventLifecycle.handle

---

before()

before(ev: E): undefined | E

Defined in: event-lifecycle.ts:41

Called before the transition is applied. May abort if returns undefined. (Represents a beforeTransition hook, not state entry/exit.)

Parameters

Parameter	Type
ev	E

Returns

undefined | E

Inherited from

EventLifecycle.before

---

update()

update(ev: E): void

Defined in: event-lifecycle.ts:45

Applies the state update.

Parameters

Parameter	Type
ev	E

Returns

void

Inherited from

EventLifecycle.update

---

effect()

effect(ev: E): void

Defined in: event-lifecycle.ts:49

Runs side effects for the transition. By default, calls leave and enter hooks.

Parameters

Parameter	Type
ev	E

Returns

void

Inherited from

EventLifecycle.effect

---

leave()

leave(ev: E): void

Defined in: event-lifecycle.ts:53

Called when leaving the previous state.

Parameters

Parameter	Type
ev	E

Returns

void

Inherited from

EventLifecycle.leave

---

enter()

enter(ev: E): void

Defined in: event-lifecycle.ts:57

Called when entering the new state.

Parameters

Parameter	Type
ev	E

Returns

void

Inherited from

EventLifecycle.enter

---

notify()

notify(ev: E): void

Defined in: event-lifecycle.ts:61

Notifies subscribers of the change.

Parameters

Parameter	Type
ev	E

Returns

void

Inherited from

EventLifecycle.notify

---

after()

after(ev: E): void

Defined in: event-lifecycle.ts:65

Final hook after transition completes. (Represents afterTransition, not state entry/exit.)

Parameters

Parameter	Type
ev	E

Returns

void

Inherited from

EventLifecycle.after

---

getState()

getState(): E["to"] | E["from"]

Defined in: state-machine.ts:31

Returns the current state of the machine (the to property of the last change).

Returns

E["to"] | E["from"]

---

getChange()

getChange(): E

Defined in: state-machine.ts:35

Returns the last change event, including type, from, and to states.

Returns

E

---

resolveExit()

resolveExit(ev: ResolveEvent<E>): undefined | E

Defined in: state-machine.ts:45

Determines the target (“to”) state for a new event. Returns undefined for early exit. Typically looks up transitions using machine.transitions[ev.from.key][ev.type].

Parameters

Parameter	Type
ev	ResolveEvent<E>

Returns

undefined | E

Properties

Property	Type	Description
send	(type: E["type"], …params: E["params"]) => void	Public API for sending an event to the machine. Parameters are attached to the event and forwarded through the transition lifecycle as .params.