我安装了Angular 5 / CLI 1.5.0：
Angular CLI: 1.5.0
Node: 8.7.0
OS: win32 x64
Angular: 5.0.1
... animations, common, compiler, compiler-cli, core, forms
... http, language-service, platform-browser
... platform-browser-dynamic, router
@angular/cli: 1.5.0
@angular-devkit/build-optimizer: 0.0.32
@angular-devkit/core: 0.0.20
@angular-devkit/schematics: 0.0.35
@ngtools/json-schema: 1.1.0
@ngtools/webpack: 1.8.0
@schematics/angular: 0.1.2
typescript: 2.4.2
webpack: 3.8.1
我创建了一个测试项目wint ng new并立即运行ng serve：
ng serve
** NG Live Development Server is listening on localhost:4200, open your browser on http://localhost:4200/ **
Date: 2017-11-08T22:24:20.928Z
Hash: 52facc1fd1cf476d4b1b
Time: 8407ms
chunk {inline} inline.bundle.js (inline) 5.79 kB [entry] [rendered]
chunk {main} main.bundle.js (main) 20.5 kB [initial] [rendered]
chunk {polyfills} polyfills.bundle.js (polyfills) 550 kB [initial] [rendered]
chunk {styles} styles.bundle.js (styles) 33.6 kB [initial] [rendered]
chunk {vendor} vendor.bundle.js (vendor) 7.02 MB [initial] [rendered]
由于某种原因，它不会生成.map文件以允许在浏览器中进行调试。使用Angular 4就可以了。
如何解决这个问题？