title: Changing every value in a hash in Ruby
body: <p>I want to change every value in a hash so as to add '%' before and after the value so</p>
  
  <pre><code>{ :a=&gt;'a' , :b=&gt;'b' }
  </code></pre>
  
  <p>must be changed to</p>
  
  <pre><code>{ :a=&gt;'%a%' , :b=&gt;'%b%' }
  </code></pre>
  
  <p>What's the best way to do this?</p>