title: Extract some JSON using Nokogiri
body: <pre><code>require 'open-uri'
  require 'json'
  require 'nokogiri'
  
  doc = Nokogiri::HTML(open("http://www.highcharts.com/demo/"))
  
  puts doc
  </code></pre>
  
  <p>But I want to be able to extract the json from this webpage, using regular expressions doesn't seem to work, and how to do extract JSON through XPath?</p>