code: func (r *route) URLWith(args []string) string {
  	if len(args) > 0 {
  		argCount := len(args)
  		i := 0
  		url := urlReg.ReplaceAllStringFunc(r.pattern, func(m string) string {
  			var val interface{}
  			if i < argCount {
  				val = args[i]
  			} else {
  				val = m
  			}
  			i += 1
  			return fmt.Sprintf(`%v`, val)
  		})
  
  		return url
  	}
  	return r.pattern
  }
docs: // URLWith returns the url pattern replacing the parameters for its values