Temporary files are a pain to deal with, and if you don't take care of them correctly you can end up with gigabytes of cached images and videos, which isn't the best use of space on a 16GB iPhone. Victor Pavlychko introduces an interesting solution to this problem – tie these files to the lifecycle of a container object.
Users don't always expect things to work the same way as the developers who created them – this is true for products as well as API designs. Analyzing the String model in Swift 3, Ole Begemann points out ways in which this API goes against the expectations of third-party developers (a large factor in the String redesign in Swift 4). API developers, take note! 🤓
Andrew Bancroft with a great 7-part series on receipt validation in Swift. Looking at this post, I didn't realize how little I knew about receipt validation – what in the world is a PKCS7 container, anyway? Should receipt validation be this complicated? Probably not, but until Apple helps to simplify the process this series should be your new reference.
One of my favorite little features announced at WWDC 2017 is the new password autofill in third-party apps. Luckily for developers, there are only three easy steps required to bring this feature to apps. This feature is currently limited to passwords stored in the iCloud Keychain, but I hope this will extend to apps like 1Password in the future. In the meantime, this is a great start 👍