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A simple library for managing state in Kotlin Multiplatform projects, using Kotlin Coroutines and `StateFlow`.

There is a newer version: 1.2.0

package dev.stateholder

/**
 * A provider of a state for a [StateHolder].
 *
 * Sometimes we can have a simple state object that does not rely on outside sources. In that case
 * you can just use [provideState], like so:
 *
 * ```
 * val stateContainer = StateContainer.create(provideState(42))
 * ```
 *
 * However sometimes we need to use a more complex state object that relies on outside sources. For
 * that we might need to inject in some dependencies and create the state object.
 *
 * ```
 * class MyRepo {
 *
 *   fun getSomeData(): Int = 42
 * }
 *
 * class MyStateProvider @Inject constructor(repo: MyRepo): StateProvider {
 *     override fun provide() = repo.getSomeData()
 * }
 *
 * class MyModel @Inject constructor(stateProvider: MyStateProvider) : ViewModel() {
 *     private val container = stateContainer(stateProvider)
 * }
 * ```
 *
 * This provides a testable way to provide state for a [StateHolder].
 */
public fun interface StateProvider {

    public fun provide(): State
}

/**
 * Convenience function to create a simple [StateProvider] with a value.
 *
 * @param[State] The type of the state.
 * @param[state] The state to provide.
 * @return A [StateProvider] that provides the [state].
 */
public fun  provideState(state: State): StateProvider = StateProvider { state }

/**
 * Convenience function to create a lazily evaluated [StateProvider].
 *
 * @param[State] The type of the state.
 * @param[block] The block that will be called to provide the state.
 * @return A [StateProvider] that provides the state returned by [block].
 */
public fun  provideState(
    block: () -> State,
): StateProvider = StateProvider { block() }

/**
 * Convenience function to create a [StateProvider] from any [T] value.
 *
 * @param[T] The type of the state.
 * @return A [StateProvider] that provides the [T] value.
 */
public fun  T.asStateProvider(): StateProvider = StateProvider { this }