build failed!Unexpected token 'export'

Creator 3.x
#1 
library\92\927deb53-6093-41bb-82e4-5e343b512062.js:182

export default (param => {

^^^^^^

SyntaxError: Unexpected token 'export'

at new Script (vm.js:101:7)

at createScript (vm.js:262:10)

at Object.runInThisContext (vm.js:310:10)

at wrapSafe (internal/modules/cjs/loader.js:974:15)

at Module._compile (internal/modules/cjs/loader.js:1034:27)

at Object.extFunction (C:\CocosDashboard\resources\.editors\Creator\3.5.2\resources\app.asar\node_modules\@editor\creator\dist\require.js:1:2163)

at Module.load (internal/modules/cjs/loader.js:935:32)

at Module._load (internal/modules/cjs/loader.js:776:14)

at Function.f._load (electron/js2c/asar_bundle.js:5:12913)

at Module.require [as __require] (internal/modules/cjs/loader.js:959:19)

构建微信小游戏提示这个，是什么错误？求救

应该是不兼容export default (param => {})写法

#2

有时候有些神奇的报错，重启小游戏工具就不报错了

#3

你是不是勾插件脚本了，插件脚本不会编译的

#4 
export default (param) => {
  return new Promise((resolve, reject) => {
    new WebsocketHeartbeat(param, {
      resolve,
      reject,
    });
  });
};

https://github.com/zimv/websocket-heartbeat-miniprogram
引入的是这个项目，微信平台。
这个找不到