react-dates/src/utils/getPooledMoment.js

A responsive and accessible date range picker component built with React

import moment from 'moment';

const momentPool = new Map();
export default function getPooledMoment(dayString) {
  if (!momentPool.has(dayString)) {
    momentPool.set(dayString, moment(dayString));
  }

  return momentPool.get(dayString);
}