For Medium Article https://medium.com/@robertsavian/generate-template-files-with-ease-19b320615359

SomeThingReducer.ts

import ISomeThingReducerState from './models/ISomeThingReducerState';
import IAction from '../IAction';
import SomeThingAction, {SomeThingActionUnion} from './SomeThingAction';
import OtherThingResponseModel from './models/OtherThingResponseModel';

export default class SomeThingReducer {
    private static readonly _initialState: ISomeThingReducerState = {
        isLoadingOtherThing: false,
        otherThing: null,
    };

    public static reducer(state: ISomeThingReducerState = SomeThingReducer._initialState, action: IAction<SomeThingActionUnion>): ISomeThingReducerState {
        switch (action.type) {
            case SomeThingAction.LOAD_OTHER_THING:
                return {
                    ...state,
                    isLoadingOtherThing: true,
                };
            case SomeThingAction.LOAD_OTHER_THING_SUCCESS:
                return {
                    ...state,
                    isLoadingOtherThing: false,
                    otherThing: action.payload as OtherThingResponseModel,
                };
            default:
                return state;
        }
    }
}