title: ArgumentError (invalid date) in Ruby On Rails
body: <p>I'm getting this ArgumentError (invalid date)
   error and can't figure out what's causing it. The method is called from javascript.</p>
  
  <pre><code>  def loadDay
       @first_day_of_week = Date.strptime("{ params[:year].to_s, :params[:month].to_s, params[:day].to_s }", "{ %Y, %m, %d }")
  
       ...
    end
  </code></pre>
  
  <p>The log looks like this:</p>
  
  <pre><code>  Started GET "/planner/loadDay?day=7&amp;month=5&amp;year=2011" for 127.0.0.1 at 2011-05-15 10:19:43 +0200
    Processing by PlannerController#loadDay as */*
    Parameters: {"day"=&gt;"7", "month"=&gt;"5", "year"=&gt;"2011"}
    Completed   in 1ms
  </code></pre>
  
  <p>Please point me in the right direction.</p>