Library-to-Library Interactions with Reactive Programming

state.js

import { from } from 'rxjs';
import { distinctUntilKeyChanged } from 'rxjs/operators';

const todoLib = createTodoLib();
const authLib = createAuthLib();

from(todoLib.state$).pipe(
  distinctUntilKeyChanged('authFailed'),
  filter(state => state.authFailed),
).subscribe(
  () => authLib.refreshAuth()
);

from(authLib.state$).pipe(
  distinctUntilKeyChanged('user'),
).subscribe(
  authState => todoLib.setUser(authState.user)
);