title: Angular 6 ERROR in Couldn't resolve original symbol for ./src/util/decorators from .../node_modules/@angular/core/core.d.ts
body: <p>I try to run the following to build my project for production and receive the error as stated in the subject:</p>
  
  <pre><code>ng build --prod
  </code></pre>
  
  <p>When I look in the core.d.ts file, it cannot find the following:</p>
  
  <pre><code>"./src/change_detection/differs/default_iterable_differ";
  "./src/profile/profile";
  "./src/util/decorators";
  </code></pre>
  
  <p>The following is the entire file:</p>
  
  <pre><code>    /**
   * Generated bundle index. Do not edit.
   */
  export * from "./index";
  export {
    APPLICATION_MODULE_PROVIDERS as ɵangular_packages_core_core_l,
    _iterableDiffersFactory as ɵangular_packages_core_core_i,
    _keyValueDiffersFactory as ɵangular_packages_core_core_j,
    _localeFactory as ɵangular_packages_core_core_k
  } from "./src/application_module";
  export {
    _appIdRandomProviderFactory as ɵangular_packages_core_core_f
  } from "./src/application_tokens";
  export {
    DefaultIterableDifferFactory as ɵangular_packages_core_core_g
  } from "./src/change_detection/differs/default_iterable_differ";
  export {
    DefaultKeyValueDifferFactory as ɵangular_packages_core_core_h
  } from "./src/change_detection/differs/default_keyvalue_differ";
  export {
    ReflectiveInjector_ as ɵangular_packages_core_core_c
  } from "./src/di/reflective_injector";
  export {
    ReflectiveDependency as ɵangular_packages_core_core_d,
    resolveReflectiveProviders as ɵangular_packages_core_core_e
  } from "./src/di/reflective_provider";
  export {
    wtfEnabled as ɵangular_packages_core_core_m
  } from "./src/profile/profile";
  export {
    createScope as ɵangular_packages_core_core_o,
    detectWTF as ɵangular_packages_core_core_n,
    endTimeRange as ɵangular_packages_core_core_r,
    leave as ɵangular_packages_core_core_p,
    startTimeRange as ɵangular_packages_core_core_q
  } from "./src/profile/wtf_impl";
  export {
    getOrCreateChangeDetectorRef as ɵangular_packages_core_core_v,
    getOrCreateContainerRef as ɵangular_packages_core_core_y,
    getOrCreateElementRef as ɵangular_packages_core_core_x,
    getOrCreateInjectable as ɵangular_packages_core_core_w,
    getOrCreateNodeInjector as ɵangular_packages_core_core_u,
    getOrCreateTemplateRef as ɵangular_packages_core_core_z
  } from "./src/render3/di";
  export {
    bindingUpdated as ɵangular_packages_core_core_ba
  } from "./src/render3/instructions";
  export {
    loadInternal as ɵangular_packages_core_core_bb
  } from "./src/render3/util";
  export {
    makeParamDecorator as ɵangular_packages_core_core_a,
    makePropDecorator as ɵangular_packages_core_core_b
  } from "./src/util/decorators";
  export { _def as ɵangular_packages_core_core_s } from "./src/view/provider";
  export {
    DebugContext as ɵangular_packages_core_core_t
  } from "./src/view/types";
  </code></pre>
  
  <p>Do I run npm i decorators? If I run the following:</p>
  
  <pre><code>ng serve --disable-host-check
  </code></pre>
  
  <p>Correction to original post - now the project does not run at all. What happened? I have been testing this thing for over a month and, now that I am ready to go live, it just does not work at all after trying to create a dist directory. WTF?</p>
  
  <p>The following is what I am seeing in the console:</p>
  
  <pre><code>TypeError: Class constructor Subject cannot be invoked without 'new'
  at new EventEmitter (core.umd.js:3597)
  at new NgZone (core.umd.js:3745)
  at getNgZone (core.umd.js:4473)
  at PlatformRef.push../node_modules/@angular/core/bundles/core.umd.js.PlatformRef.bootstrapModuleFactory (core.umd.js:4369)
  at core.umd.js:4415
  at ZoneDelegate.push../node_modules/zone.js/dist/zone.js.ZoneDelegate.invoke (zone.js:388)
  at Zone.push../node_modules/zone.js/dist/zone.js.Zone.run (zone.js:138)
  at zone.js:872
  at ZoneDelegate.push../node_modules/zone.js/dist/zone.js.ZoneDelegate.invokeTask (zone.js:421)
  at Zone.push../node_modules/zone.js/dist/zone.js.Zone.runTask (zone.js:188)
  </code></pre>
  
  <p>When I run ng build I am seeing the following:</p>
  
  <pre><code>ng build --prod
  
  Date: 2019-02-02T23:59:21.603Z
  Hash: 51184dcdbc91f92a675d
  Time: 3998ms
  chunk {0} runtime.6afe30102d8fe7337431.js (runtime) 1.05 kB [entry] [rendered]
  chunk {1} styles.42d170ae18051bd9f923.css (styles) 177 kB [initial] [rendered]
  chunk {2} polyfills.03b06938f23b8f1cb153.js (polyfills) 130 bytes [initial] [rendered]
  chunk {3} main.541dbdbf0b123b4c3be8.js (main) 128 bytes [initial] [rendered]
  
  ERROR in Couldn't resolve original symbol for ./src/util/decorators from /Applications/MAMP/htdocs/oshop/node_modules/@angular/core/core.d.ts
  </code></pre>
  
  <p>BTW, now in app.module.ts, it cannot find module for HttpClientModule or HTTP_INTERCEPTORS </p>
  
  <pre><code>Cannot find module '@angular/common/http' 
  </code></pre>
  
  <p>When I try to re-install @angular/common:</p>
  
  <pre><code>sudo npm i -g @angular/common^6.1.10
  npm ERR! code ENOLOCAL
  npm ERR! Could not install from "@angular/common^6.1.10" as it does not contain a package.json file.
  
  npm ERR! A complete log of this run can be found in:
  npm ERR!     /Users/tam3/.npm/_logs/2019-02-03T02_29_27_361Z-debug.log
  </code></pre>
  
  <p>But it is in the package.json:</p>
  
  <pre><code>"devDependencies": {
    "@angular-devkit/build-angular": "~0.7.0",
    "@angular/cli": "~6.1.0",
    "@angular/common": "~6.1.10",
    "@angular/compiler-cli": "^6.1.0",
    "@angular/core": "^6.1.10",
  </code></pre>
  
  <p>WTF, I followed a post that suggested all I had to do was to trash the node_modules directory, followed by npm install and it would reinstall everything. What can I do? I literally was ready to go live today</p>
  
  <p>Thanks in advance</p>