Marker Interfaces

PulseMVI uses marker interfaces to enforce type safety at the generic level. Each interface has no members — they exist solely to constrain type parameters.

PulseState

interface PulseState

Marks a class as the UI state managed by a PulseStore. Implement with a data class so copy() is available for immutable updates.

data class CounterState(
    val count: Int = 0,
    val isLoading: Boolean = false,
) : PulseState

---

PulseAction

interface PulseAction

Marks a class as a user intent dispatched to a PulseStore. Implement with a sealed class to enumerate all possible actions exhaustively.

sealed class CounterAction : PulseAction {
    data object Increment : CounterAction()
    data object Decrement : CounterAction()
    data class SetValue(val value: Int) : CounterAction()
}

---

PulseEvent

interface PulseEvent

Marks a class as a one-time side effect emitted from a PulseStore to the UI. Implement with a sealed class.

sealed class CounterEvent : PulseEvent {
    data class ShowMessage(val message: String) : CounterEvent()
    data object NavigateBack : CounterEvent()
}

---

PulseBroadcast

interface PulseBroadcast

Marks a class as a broadcast message delivered by PulseContainer to all registered PulseStore instances. Implement with a sealed class.

sealed class AppBroadcast : PulseBroadcast {
    data object UserLoggedOut : AppBroadcast()
    data class ThemeChanged(val isDark: Boolean) : AppBroadcast()
}