Bridging Existentials & Generics in Swift 2

We are back to another episode of discussing generics, protocols with associated types and some type system limitations in Swift 2. This time we will dive into an interesting workaround that the infamous jckarter has taught me. We will also discuss how this workaround might become unnecessary through enhanced existential support in future Swift versions. But what are existentials anyway?


Real World Flux Architecture on iOS

About half a year ago we started adopting the Flux architecture in the PlanGrid iOS app. This post will discuss our motivation for transitioning from traditional MVC to Flux and will share the experience we have gathered so far.

I’m attempting to describe large parts of our Flux implementation by discussing code that is in production today. If you’re only interested in the high level conclusion you can skip the middle part of this post.


GCD's Main Queue vs. Main Thread

The correct way to ensure that code runs on the main thread / main queue is a recurring issue that causes some confusion among Cocoa developers. The topic came up again this week as part of an issue with ReactiveCocoa and MapKit:


Beware the UIKit Visitors!

Investigating the Cause of Quadratic Time Complexity When Adding Subviews in UIKit

Yesterday Two weeks ago we identified a performance regression in the PlanGrid app, when entering a view that dynamically adds a large amount of subviews.

I started this blog post back then, but was recently motivated to finish it quickly by seeing other developers running into this issue as well:


Decoding Heterogeneous Collections in Swift

The problem of decoding Swift types from an outside data source, such as JSON, has been mostly solved. Since Swift’s release we’ve seen more than a dozen popular JSON mapping libraries pop up.

However, most of the libraries I’ve seen so far deal with decoding individual types, not entire collections of heterogeneous types.


Compile Time vs. Run Time Type Checking in Swift

At some point, when learning how to use Swift’s type system, it is important to understand that Swift (like many other languages) has two different forms of type checking: static and dynamic. Today I want to briefly discuss the difference between them and why headaches might arise when we try to combine them.