/**
 * main.js
 */

'use strict';

// Only run in capable browsers via feature detection
var didCutTheMustard = 'querySelector' in document
  && 'classList' in document.createElement('a')
  && 'addEventListener' in window;

if (didCutTheMustard) {

  // Add class "js" to html element
  document.querySelector('html').classList.add('js');

  /**
   * Add line numbers to <pre>
   */
  (function () {
    var pre = document.querySelectorAll('pre'),
        pl = pre.length;

    for (var i = 0; i < pl; i++) {
      pre[i].insertAdjacentHTML('beforeend', '<span class="ln" aria-hidden="true"></span>');
      var num = pre[i].innerHTML.split(/\n/).length;

      // Start counter at 1 to circumvent Jekyll adding an extra line in <code>
      for (var j = 1; j < num; j++) {
        var lineNum = pre[i].querySelector('.ln');
        lineNum.insertAdjacentHTML('beforeend', '<span></span>');
      }
    }
  })();
}

/**
 * main.js
 *
 * We keep things simple here in the countryside. No complex
 * module loading or whatever using Browserify or RequireJS.
 * Just one plain, simple vanilla JavaScript file.
 */

'use strict';

// Only run in capable browsers via feature detection
var didCutTheMustard = 'querySelector' in document
  && 'classList' in document.createElement('a')
  && 'addEventListener' in window;

if (didCutTheMustard) {

  // Add class "js" to html element
  document.querySelector('html').classList.add('js');

  /**
   * Add line numbers to <pre>
   */
  (function () {
    var pre = document.querySelectorAll('pre'),
        pl = pre.length;

    for (var i = 0; i < pl; i++) {
      pre[i].insertAdjacentHTML('beforeend', '<span class="ln" aria-hidden="true"></span>');
      var num = pre[i].innerHTML.split(/\n/).length;

      // Start counter at 1 to circumvent Jekyll adding an extra line in <code>
      for (var j = 1; j < num; j++) {
        var lineNum = pre[i].querySelector('.ln');
        lineNum.insertAdjacentHTML('beforeend', '<span></span>');
      }
    }
  })();
}

Add superflous commenting to JS
Add superflous commenting to JS
