title: delete_if returning undefined method `include?' for nil:NilClass
body: <p>Not sure why this is happening, I'm just using the method how I see it here: <a href="https://apidock.com/ruby/Array/delete_if" rel="nofollow noreferrer">delete_if</a></p>
  
  <p>But obviously I'm doing something wrong, just can't tell what.</p>
  
  <p>This is my code:</p>
  
  <pre><code>non_enabled_speeds = ["Expedited", "Standard"]
  
  parsed_rates = [{:service_name=&gt;"Expedited",
    :service_code=&gt;"XYZ", :total_price=&gt;800, :currency=&gt;"USD"}, 
    {:service_name=&gt;"Priority", :service_code=&gt;"PYT", 
  :total_price=&gt;1300, :currency=&gt;"USD"},
    {:service_name=&gt;"Standard", :service_code=&gt;"XYZ", 
  :total_price=&gt;500, :currency=&gt;"USD"}]
  
  non_enabled_speeds.each do |non_enabled_rate|
    parsed_rates.delete_if 
  {|rate| rate[:speed].include?(non_enabled_rate)}
  end
  </code></pre>
  
  <p>I understand that <code>delete_if</code> uses <code>include?</code> under the covers, but I'm not sure why I'm getting this error:</p>
  
  <pre><code>undefined method `include?' for nil:NilClass
  </code></pre>