// Action creator function setUserName(userName) { return { // Action type: 'SET_USER_NAME', UserName, }; } このActionCreatorですが、どういったものなのか公式ドキュメントでは下記のようにあります。 Actions · Redux (参照日: 2017/09/01) Action creators are exactly that—functions that create actions. It's easy to conflate the terms “action” and “action creator,” so do your best to use the proper term. In Redux action creators simply return a