安装第一个软件包时，我有两个软件包ngx-infinite-scroll和ngx-bar-rating，第二个软件包被删除了。如果安装第二个，也是一样。
Angular CLI: 7.1.4
Node: 8.9.4
OS: win32 x64
Angular: 7.1.4
... cli, common, compiler, compiler-cli, core, forms
... language-service, platform-browser, platform-browser-dynamic
... router
Package Version
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@angular-devkit/architect 0.11.4
@angular-devkit/build-angular 0.11.4
@angular-devkit/build-optimizer 0.11.4
@angular-devkit/build-webpack 0.11.4
@angular-devkit/core 7.1.4
@angular-devkit/schematics 7.1.4
@angular/animations 7.2.0
@angular/cdk 7.2.1
@angular/material 7.2.1
@ngtools/webpack 7.1.4
@schematics/angular 7.1.4
@schematics/update 0.11.4
rxjs 6.3.3
typescript 3.1.6
webpack 4.23.1