number-munchers/reducers/welcome/new-game.reducer.js

import * as NewGameActions from '../../actions/welcome/new-game.actions';

const initial = { hidden: false };
const reducer = (state = initial, action) => {
    if (action.type !== NewGameActions.NEWGAME_ACTION) {
        return state;
    }

    if (action.action === NewGameActions.BLINK) {
        return (state.hidden ? { hidden: false } : { hidden: true });
    }

    return state;
};

export default reducer;