title: Regular Expression to select text between curly braces, Ruby
body: <p>I'm working on a way to filter and replace broken curly brace tags such as <code>{{hello}</code>. I've tried out a few regular expressions from here in Stack and tried on my own. The closes I've come is using this regex 
  <code>(?=(\}(?!\})))((?&lt;!\})\})</code> which selects the last tag in the example code block below. However it does not select the entire tag, it just selects the ending curly brace <code>}</code>.</p>
  
  <pre><code>{{hello}}
  {{world}}}
  {{foobar}}
  {{hello}
  </code></pre>
  
  <p>What I need to do is select any tag that is missing the second ending curly brace like <code>{{hello}</code>. Can anyone help me with the regex to select this type of tag?</p>