title: How does ActiveRecord::Base "find_by_" method work?
body: <p>I'm looking to create a function that works similarly to the way <code>ActiveRecord::Base</code>'s <code>find_by_'column_name'</code> works. For example, if I do something like </p>
  
  <p><code>User.find_by_address("1234 Apple Road")</code></p>
  
  <p>it will look up via the <code>address</code> column. But I'm perplexed as to how it works. </p>
  
  <p>I see both <code>self.prefix</code> and <code>self.suffix</code> when I look at the code for "dynamic matchers" in the code, e.g. <a href="https://github.com/rails/rails/blob/master/activerecord/lib/active_record/dynamic_matchers.rb#L101" rel="nofollow">here</a>, but in my research I can't find anything about <code>self.prefix</code> or <code>self.suffix</code> for Ruby.</p>
  
  <p>How would I create this kind of function?</p>