Q:

Export / import sub folder from Angular Library

I am working with an Angular library that uses public-api.ts to export the elements of the application so other consuming applications can use them. For example:
public-api.ts:
export * from './lib/core.module';
export * from './lib/components/header/header.component';
export * from './lib/components/layout/layout.component';
export * from './lib/components/tenant-nav/tenant-nav.component';
export * from './lib/components/left-menu/left-menu.component';
export * from './lib/services/config-resolver.service';
export * from './lib/common/types';
export * from './lib/common/const';

I have a folder lib/common/const that contains files that export constants. This is one file for example:
export const LEFT_MENU_EVENT = 'Base.Menu.LeftMenuEvent';
export const APP_MENU_EVENT = 'Base.Menu.AppMenuEvent';

In my library I can import the variables from one specific file using 
import * as CONSTANTS from './constants/myfile'

I wish to only import the constants file from my library in my consuming app. Here is the statement I wish to work:
import * as CONSTANTS from '@mylibrary/const'

How can this be done? It seems like everything that is exported in the public-api.ts file is flattened. I wish to reference a subfolder in my library similiar to 
import { Component } from '@angular/core'

A:

I found a way to export a file as a namespace instead of exporting a subfolder. This did the trick:
export * from './lib/core.module';
...
import * as ALL_KEYS from './lib/common/const';
export { ALL_KEYS };

Then I imported as:
import { ALL_KEYS } from '@mylibrary';

