A tiny example of an application state management done in a fully functional manner

functionalDispatch.js

const getDispatch = (initialState, render) => {
    let stateContainer = Container.of(initialState);

    const updateState = action => new IO(() => {
        stateContainer = stateContainer.map(action);
        return stateContainer;
    });

    return action => {
        const sideEffects = pipe(
            updateState,
            chain(containerToIO),
            chain(render)
        )(action);
        sideEffects.performUnsafeIO();
    };
};