> require('promise-js')
{ [Function: Promise]
all: [Function],
cast: [Function],
race: [Function],
reject: [Function],
resolve: [Function] }
> require('core-js')
TypeError: Cannot redefine property: Symbol(Symbol.iterator)
at Object.defineProperty [as setDesc] (native)
at module.exports.object.(anonymous function) (/home/seagull/huaban/muse/node_modules/core-js/modules/$.hide.js:4:12)
at module.exports (/home/seagull/huaban/muse/node_modules/core-js/modules/$.iter-define.js:50:5)
at Object.<anonymous> (/home/seagull/huaban/muse/node_modules/core-js/modules/es6.array.iterator.js:11:44)
at Module._compile (module.js:460:26)
at Object.Module._extensions..js (module.js:478:10)
at Module.load (module.js:355:32)
at Function.Module._load (module.js:310:12)
at Module.require (module.js:365:17)
at require (module.js:384:17)
