title: Array select with multiple conditions ruby
body: <p>I can do:</p>
  
  <pre><code>@items = @items.select {|i| i.color == 'blue'}
  @items = @items.select {|i| i.color == 'blue' || i.color == 'red'}
  </code></pre>
  
  <p>What if I am given an unknown amount of colors and I want to select them all? i.e.</p>
  
  <pre><code>['red','blue','green','purple']
  # or
  ['blue','red']
  </code></pre>
  
  <p>I've been working on a mess of code that creates several temporary arrays and then merges or flattens them into one, but I'm really unhappy with it.</p>