title: Ctor is not a constructor
body: <p>I'm trying to build the production version of my web app developed in angular7 and the compilation runs fine. But when I try to navigate to the app an error in console is raised:</p>
  
  <pre><code>Uncaught TypeError: ctor is not a constructor
      at _createClass (main.07add232d9f568bb2d7a.js:33609)
      at _createProviderInstance (main.07add232d9f568bb2d7a.js:33583)
      at initNgModule (main.07add232d9f568bb2d7a.js:33514)
      at new NgModuleRef_ (main.07add232d9f568bb2d7a.js:34243)
      at Object.createNgModuleRef (main.07add232d9f568bb2d7a.js:34232)
      at NgModuleFactory_.push../node_modules/@angular/core/fesm5/core.js.NgModuleFactory_.create (main.07add232d9f568bb2d7a.js:36793)
      at main.07add232d9f568bb2d7a.js:30443
      at ZoneDelegate.push../node_modules/zone.js/dist/zone.js.ZoneDelegate.invoke (polyfills.a8a979dc29215b620775.js:396)
      at Object.onInvoke (main.07add232d9f568bb2d7a.js:29978)
      at ZoneDelegate.push../node_modules/zone.js/dist/zone.js.ZoneDelegate.invoke (polyfills.a8a979dc29215b620775.js:395)
  </code></pre>
  
  <p>How can I fix it? I can't understand which library is going wrong. This is my package.json</p>
  
  <pre><code>{
    "name": "cop-ang",
    "version": "0.0.0",
    "scripts": {
      "ng": "ng",
      "start": "ng serve",
      "build": "ng build",
      "test": "ng test",
      "lint": "ng lint",
      "e2e": "ng e2e"
    },
    "private": true,
    "dependencies": {
      "@angular/animations": "^7.1.4",
      "@angular/common": "^7.1.4",
      "@angular/compiler": "^7.1.4",
      "@angular/core": "^7.1.4",
      "@angular/forms": "^7.1.4",
      "@angular/http": "^7.1.4",
      "@angular/platform-browser": "^7.1.4",
      "@angular/platform-browser-dynamic": "^7.1.4",
      "@angular/router": "^7.1.4",
      "@ng-bootstrap/ng-bootstrap": "^4.0.1",
      "angular-intl-tel-input": "0.0.9",
      "bootstrap": "^4.2.1",
      "core-js": "^2.6.1",
      "google-libphonenumber": "^3.2.2",
      "intl-tel-input": "^14.0.6",
      "jquery": "^3.3.1",
      "ngx-bootstrap": "^3.1.4",
      "npm-check-updates": "^2.15.0",
      "popper.js": "^1.14.6",
      "rxjs": "^6.3.3",
      "ts-md5": "^1.2.4",
      "zone.js": "^0.8.26"
    },
    "devDependencies": {
      "@angular-devkit/build-angular": "^0.11.4",
      "@angular/cli": "^7.1.4",
      "@angular/compiler-cli": "^7.1.4",
      "@angular/language-service": "^7.1.4",
      "@types/jasmine": "^3.3.5",
      "@types/jasminewd2": "^2.0.6",
      "@types/jquery": "^3.3.29",
      "@types/node": "^10.12.18",
      "angular-ide": "^0.9.55",
      "codelyzer": "~4.5.0",
      "jasmine-core": "~3.3.0",
      "jasmine-spec-reporter": "~4.2.1",
      "karma": "^3.1.4",
      "karma-chrome-launcher": "~2.2.0",
      "karma-coverage-istanbul-reporter": "^2.0.4",
      "karma-jasmine": "~2.0.1",
      "karma-jasmine-html-reporter": "^1.4.0",
      "protractor": "^5.4.2",
      "ts-node": "~7.0.1",
      "tslint": "~5.12.0",
      "typescript": "3.1.6"
    }
  }
  </code></pre>
  
  <p>And this is the app.module.ts:</p>
  
  <pre><code>import { NgbDateCustomParserFormatter } from './customformatters/NgbDateCustomParserFormatter';
  import { WorkshiftComponent } from './protectedpages/workshift/workshift.component';
  import { BrowserModule } from '@angular/platform-browser';
  import { LOCALE_ID, NgModule } from '@angular/core';
  
  import { AppComponent } from './app.component';
  import { AppRoutingModule } from './app-routing.module';
  import { IntegerDirective } from './customdirectives/integerdirective';
  import { FormsModule } from '@angular/forms';
  import { HttpClientModule } from '@angular/common/http';
  import { BrowserAnimationsModule } from '@angular/platform-browser/animations';
  import { IndexComponent } from './publicpages/index/index.component';
  import { RegisterComponent } from './publicpages/register/register.component';
  import { ReactiveFormsModule } from '@angular/forms';
  import { ActivateComponent } from './protectedpages/activate/activate.component';
  import { LoginComponent } from './publicpages/login/login.component';
  import { ConfigureirComponent } from './protectedpages/configureir/configureir.component';
  import { ServicesComponent } from './protectedpages/services/services.component';
  import { ConfigureuserComponent } from './protectedpages/configureuser/configureuser.component';
  import { NavmenuComponent } from './protectedpages/navmenu/navmenu.component';
  import { NewServiceComponent } from './protectedpages/newservice/newservice.component';
  import { TildeStringPipe } from './custompipes/tildestring.pipe';
  import { ServiceComponent } from './protectedpages/service/service.component';
  import { NgbModule, NgbDateParserFormatter } from '@ng-bootstrap/ng-bootstrap';
  import { UsersComponent } from './protectedpages/users/users.component';
  import { NewuserComponent } from './protectedpages/newuser/newuser.component';
  import { ChangePasswordComponent } from './protectedpages/changepassword/changepassword.component';
  import { CommaStringPipe } from './custompipes/commastring.pipe';
  import { UserComponent } from './protectedpages/user/user.component';
  import { VehiclesComponent } from './protectedpages/vehicles/vehicles.component';
  import { VehicleComponent } from './protectedpages/vehicle/vehicle.component';
  import { NewVehicleComponent } from './protectedpages/newvehicle/newvehicle.component';
  import { NewWorkshiftComponent } from './protectedpages/newworkshift/newworkshift.component';
  import { WorkshiftsComponent } from './protectedpages/workshifts/workshifts.component';
  import { PublicnavmenuComponent } from './publicpages/publicnavmenu/publicnavmenu.component';
  import { WhatisComponent } from './publicpages/whatis/whatis.component';
  import { WhyComponent } from './publicpages/why/why.component';
  import { PricesComponent } from './publicpages/prices/prices.component';
  import { FaqComponent } from './publicpages/faq/faq.component';
  import { LogoutComponent } from './publicpages/logout/logout.component';
  import { BsDropdownModule } from 'ngx-bootstrap/dropdown';
  import { IntlTelInputModule } from 'angular-intl-tel-input';
  
  // Locale IT
  import { registerLocaleData } from '@angular/common';
  import localeIt from '@angular/common/locales/it';
  
  registerLocaleData(localeIt, 'it');
  
  @NgModule({
    declarations: [
      AppComponent,
      IndexComponent,
      RegisterComponent,
      ActivateComponent,
      LoginComponent,
      ConfigureirComponent,
      ServicesComponent,
      ConfigureuserComponent,
      NavmenuComponent,
      NewServiceComponent,
      TildeStringPipe,
      IntegerDirective,
      ServiceComponent,
      UsersComponent,
      NewuserComponent,
      ChangePasswordComponent,
      CommaStringPipe,
      UserComponent,
      VehiclesComponent,
      VehicleComponent,
      NewVehicleComponent,
      NewWorkshiftComponent,
      WorkshiftsComponent,
      WorkshiftComponent,
      PublicnavmenuComponent,
      WhatisComponent,
      WhyComponent,
      PricesComponent,
      FaqComponent,
      LogoutComponent
    ],
    imports: [
      BrowserModule,
      AppRoutingModule,
      FormsModule,
      HttpClientModule,
      BrowserAnimationsModule,
      ReactiveFormsModule,
      NgbModule,
      BsDropdownModule.forRoot(),
      IntlTelInputModule
    ],
    providers: [{ provide: LOCALE_ID, useValue: 'it'}, {provide: NgbDateParserFormatter, useValue: NgbDateCustomParserFormatter}],
    bootstrap: [AppComponent]
  })
  export class AppModule { }
  </code></pre>