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Redux implementation for Kotlin. Mulitiplatform supported.

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package org.reduxkotlin

/**
 * Creates a store enhancer that applies middleware to the dispatch method
 * of the Redux store. This is handy for a variety of tasks, such as expressing
 * asynchronous actions in a concise manner, or logging every action payload.
 *
 * See `redux-thunk` package as an example of the Redux middleware.
 *
 * Because middleware is potentially asynchronous, this should be the first
 * store enhancer in the composition chain.
 *
 * Note that each middleware will be given the `dispatch` and `getState` functions
 * as named arguments.
 *
 * @param {vararg Middleware} [middleware] The middleware chain to be applied.
 * @returns {StoreEnhancer} A store enhancer applying the middleware.
 */
fun  applyMiddleware(vararg middlewares: Middleware): StoreEnhancer {
    return { storeCreator ->
        { reducer, initialState, en: Any? ->
            val store = storeCreator(reducer, initialState, en)
            val origDispatch = store.dispatch
            val dispatch: Dispatcher = {
                throw Exception(
                    """Dispatching while constructing your middleware is not allowed.
                    Other middleware would not be applied to this dispatch.""")
            }
            store.dispatch = dispatch
            val chain = middlewares.map { middleware -> middleware(store) }
            store.dispatch = compose(chain)(origDispatch)
            store
        }
    }
}