Module parse failed: Unexpected token

[meceway]

Module parse failed: Unexpected token (51:9)
You may need an appropriate loader to handle this file type, currently no loaders are configured to process this file. See https://webpack.js.org/concepts#loaders
| // src/workbook.ts
| var WorkBook = class {

Sheets = {};
| SheetNames = [];
| };

here code is const xlsx = require('node-xlsx')

what happend ?