title: Convert HTML to plain text in Swift (without using NSAttributedString)
body: <p>I need to convert some HTML into plain text and have tried the approaches outlined here:</p>
  
  <p><a href="https://stackoverflow.com/questions/28124119/convert-html-to-plain-text-in-swift">Convert HTML to Plain Text in Swift</a></p>
  
  <p>The problem is that on iOS 8.2, NSAttributedString has a bug which can result in a EXC_BAD_ACCESS crash (deep inside WebKit) when HTML is rendered to plain text on a background thread. The conversion needs to be done on a background thread because it can (and usually does) take a while.</p>
  
  <p>So I need a more primitive solution in Swift, ideally an idiomatic one.</p>
  
  <p>It also strikes me that this is probably one of those problems which has an elegant and neat functional solution - it's essentially a <code>filter()</code> operation on a String surely?</p>