关于ramda.js引包的问题

Question

框架是react,  脚手架为dva官方脚手架下面是模块共享数据文件 ==>modle/todos.jsconst R = require('ramda')    //<===== // import R from 'ramda'      //<=====   export default { namespace: 'todos', state: {     'list': [         {             'title': '吃饭',             'done': true         },         {             'title': '睡觉',             'done': false         },         {             'title': '拉屎',             'done': false         }     ],     'visible': 0, }, effects: { }, reducers: {     change_todo(state, action) {         return R.set(R.lensProp('visible'), action.visible, state)     }, }, };为什么将引包方式换成 import R from 'ramda'后会报错, 报错内容为TypeError: Cannot read property 'set' of undefined