code: function compileKeys(urls) {
      return urls.map(function (url) {
          // replace named params with regexp groups
          var pattern = url[0].replace(/\/:\w+/g, '(?:/([^\/]+))');
          url[0] = new RegExp('^(?:' + pattern + ')$');
          return url;
      });
  }
docs: /*
  Compiles the url patterns to a reqular expression, returning an array
  of arrays.
  
  compileKeys([['abc', 'GET', function () {}], ['xyz', 'POST', function () {}]])
  [[/^abc$/, 'GET', function () {}], [/^xyz$/, 'POST', function () {}]]