switchless reducers

example.js

import addHandler from './helper'
import {UPDATE_PENDING, UPDATE_LOADED, UPDATE_FAILED} from './actions';

const initialState = {};

// Handlers
const onUpdatePending = (state) => state
const onUpdateLoaded  = (state, json) => Object.assign({}, state, json);
const onUpdateFailed  = (state, err) => state;

// Store
export default addHandlers(initialState, {
  [UPDATE_PENDING]: onUpdatePending,
  [UPDATE_LOADED]: onUpdateLoaded,
  [UPDATE_FAILED]: onUpdateFailed
});

helper.js

export default (initialState, handlers) =>
  (state = initialState, action) =>
    handlers[action.type]
      ? handlers[action.type](state, action.payload)
      : state;

index.js

import { combineReducers } from 'redux';

import example from './example';

export default combineReducers({example});