Angular -如何在启动时诊断'SyntaxError:意外令牌<‘致命错误

Question

我已经有过几次这样的模糊错误，每次都是在修改了我的Angular (2-5)依赖项之后。

SyntaxError: Unexpected token <
    at eval (<anonymous>)
    at evaluate (http://localhost:5557/node_modules/systemjs/dist/system.src.js?1512143707276:2818:16)
    at http://localhost:5557/node_modules/systemjs/dist/system.src.js?1512143707276:3621:21
    at dynamicExecute (http://localhost:5557/node_modules/systemjs/dist/system.src.js?1512143707276:1142:26)
    at doEvaluate (http://localhost:5557/node_modules/systemjs/dist/system.src.js?1512143707276:1089:13)
    at ensureEvaluate (http://localhost:5557/node_modules/systemjs/dist/system.src.js?1512143707276:997:13)
    at http://localhost:5557/node_modules/systemjs/dist/system.src.js?1512143707276:1015:20
    at Object.eval (http://localhost:5557/app/app.module.js:15:14)
    at eval (http://localhost:5557/app/app.module.js:69:4)
    at eval (http://localhost:5557/app/app.module.js:70:3)

从哪里开始了解到底发生了什么？