title: Compilation error in Angular app with version 12 try to use a angular library built in Angular 10
body: <p>I've a sample Angular app built with version 12. When this app try to use a library built with Angular 10 and compile the code I get below compilation error. Any help on this is appreciated. This is part of a POC on an app using libraries built with older versions as our application is expected to be in this state eventually.</p>
  <p>Error: node_modules/practice10/lib/practice10lib.module.d.ts:5:21 - error TS2694: Namespace '&quot;C:/src/spaexample/axcess-spa-mainapp/node_modules/@angular/core/core&quot;' has no exported member 'ɵɵNgModuleDefWithMeta'.</p>
  <p>5     static ɵmod: i0.ɵɵNgModuleDefWithMeta&lt;Practice10libModule, [typeof i1.Practice10libComponent], [typeof i2.AgGridModule], [typeof i1.Practice10libComponent]&gt;;
  ~~~~~~~~~~~~~~~~~~~~~</p>
  <p>Error: node_modules/practice10/lib/practice10lib.service.d.ts:4:21 - error TS2694: Namespace '&quot;C:/src/spaexample/axcess-spa-mainapp/node_modules/@angular/core/core&quot;' has no exported member 'ɵɵFactoryDef'.</p>
  <p>4     static ɵfac: i0.ɵɵFactoryDef&lt;Practice10libService, never&gt;;
  ~~~~~~~~~~~~</p>
  <p>mError: node_modules/practice10/lib/practice10lib.service.d.ts:5:22 - error TS2724: '&quot;C:/src/spaexample/axcess-spa-<em>mainapp/node_modules/@angular/core/core&quot;' has no exported member named 'ɵɵInjectableDef'. Did you mean 'ɵgetInjectableDef'?</em></p>
  <p>5     static ɵprov: i0.ɵɵInjectableDef;</p>