Root Selectors

selectors.ts

import { createSelector, MemoizedSelector } from '@ngrx/store';
import {
  MyFeatureStoreSelectors
} from './my-feature-store';

import {
  MyOtherFeatureStoreSelectors
} from './my-other-feature-store';

export const selectError: MemoizedSelector<object, string> = createSelector(
  MyFeatureStoreSelectors.selectMyFeatureError,
  MyOtherFeatureStoreSelectors.selectMyOtherFeatureError,
  (myFeatureError: string, myOtherFeatureError: string) => {
    return myFeature || myOtherFeature;
  }
);

export const selectIsLoading: MemoizedSelector<
  object,
  boolean
> = createSelector(
  MyFeatureStoreSelectors.selectMyFeatureIsLoading,
  MyOtherFeatureStoreSelectors.selectMyOtherFeatureIsLoading,
  (myFeature: boolean, myOtherFeature: boolean) => {
    return myFeature || myOtherFeature;
  }
);

i feel that:
return myFeature || myOtherFeature;

should be:
return myFeatureError || myOtherFeatureError;

i feel that:
return myFeature || myOtherFeature;

should be:
return myFeatureError || myOtherFeatureError;

yes, it should be.