title: How to create KOA route with both parameter and regex
body: <p>How can I accomplish the following KOA route handler:</p>
  
  <pre><code>app.get("/Chicago_Metro/Cicero_City", myFunctionHandler1)
  app.get("/Cook_County/Cicero_City", myFunctionHandler2)
  </code></pre>
  
  <p>and end up with "Chicago" as the parameter to be passed for "metro" OR "Cook" passed for county and "Cicero" passed for "city in my handlers below:</p>
  
  <pre><code>function *myFunctionHandler1(metro, city) {
  ...
  }
  
  function *myFunctionHandler2(county, city) {
  ...
  }
  </code></pre>
  
  <p>I was considering Regex in the route but I never saw how that can mix with :param.</p>
  
  <p>NOTE: I need to keep that path syntax since it's already SEO'ed and indexed as above.</p>
  
  <p>Worst case probably I will end up with the whole name as parameter and handle it inside a single handlerFn and test the ending to _metro or _county or _city</p>