Spent at huge part of the hour today troubleshooting why my API change to an init method was not being seen by the playground. Weird caching bugs? No; it turns out that XCode was building for target instead of simulator, so the playground didn’t get a rebuilt version of the framework when I hit build. Still don’t know why that changed since last time, but oh well.

After that frustration was cleared I proceeded to learn that Swift has the same semi-dynamic Array notion as Objective C has, so they need to be properly managed with respect to reserving space and inserting new objects.