A couple of weeks ago, I ran into a peculiar problem that I think might be useful to talk about. It took me a bunch of googling and hacking around to find a solution — hopefully it will save someone else some time in the future. Here’s a simplistic version of the problem. Let’s say we want to store and display user profile information in our web application. The user profile has a list of locations they’ve lived in the past. A location comprises a city and country. In JSON notation, it would look like this: