reselect-example.js

var { createStructuredSelector } = require("reselect")

const ide = {
  tabs: [],
  activeTab: null,
  sidebarInitialSize: 100,
  sidebarTab: 'schema',
  contents: {},
};

const selector = createStructuredSelector({
  tabs: state => state.tabs,
  activeTab: state => state.activeTab,
  sidebarInitialSize: state => state.sidebarInitialSize,
  sidebarTab: state => state.sidebarTab,
});

console.log(selector(ide) === selector({ ...ide, contents: { test: 1 } }));