Useful set of JavaScript snippets

snippets.js

// Replace extra spaces with single ones and get rid of any spaces at the end and beginning of the string.
// http://stackoverflow.com/questions/6163169/replace-multiple-whitespaces-with-single-whitespace-in-javascript-string - Marku Uttula's answer
var s = " too much  trailing space "
s = s.replace(/^(\s*)|(\s*)$/g, '').replace(/\s+/g, ' ');

// Determining the base font size, so that we can use em and rem units in JS
// TODO - make it foolproof and compatible with browsers, which handle `getComputedStyle()`
function getDefaultFontSize() {
  var el = document.body.appendChild(document.createElement('p'));
  el.innerHTML = 'size matters';
  el.style['font-size'] = '1em';
  var fontSize = document.defaultView.getComputedStyle(el).fontSize;
  document.body.removeChild(el);
  return fontSize.substring(0, fontSize.indexOf('px'));
};