'use strict';

const puppeteer = require('puppeteer');

(async function main() {
  try {
    const browser = await puppeteer.launch();
    const [page] = await browser.pages();

    await page.goto('https://example.org/');

    const allElements = await page.evaluateHandle(
      () => [...document.querySelectorAll('*')]
    );

    const numberOfElements = await page.evaluate(
      elements => elements.length, allElements
    );

    console.log(numberOfElements);

    await browser.close();
  } catch (err) {
    console.error(err);
  }
})();