leafReducerFabric.js

export function createLeafReducer(initialState, HANDLERS) {
    return function leafReducer(state, action) {
        if (typeof state === 'undefined') return initialState;
        
        const HANDLER = HANDLERS[action.type];

        if (typeof HANDLER === 'undefined') return state;
        if (typeof HANDLER !== 'function') return HANDLER;

        var newState;
        try {
            newState = HANDLER.call(HANDLERS, state, action);
        } catch (err) {
            console.error('Ошибка в обработке ивента ' + action.type, err);
        }
        return typeof newState === 'undefined' ? state : newState;
    }
}