Open external links in a new window using JavaScript

It is good practise to open external links in a new window. However, it can be a bit tedious to remember to include target="_blank", especially in Markdown. To get around this, I have incorporated a simple raw JavaScript solution, which can be found below.

for (var links = document.getElementsByTagName('a'), i = 0, l = links.length; i < l; i++) {
  var link = links[i];
  if (link.getAttribute('href') && link.hostname !== location.hostname) link.target = '_blank';
}

If you have access to jQuery on the page, then a more elegant solution presented below would be more appealing.

$('a[href^="http"]')
  .not('[href*="' + location.hostname + '"]')
  .attr('target', '_blank');