I just left a hipster coffee shop. It was packed with iOS devs, whispering amongst each other about how they can’t wait for Apple to release an official style guide and formatter for Swift. Lately, the community has been buzzing about the proposal from Tony Allevato and Dave Abrahams to adopt an official style guide and formatting tool for the Swift language. Hundreds of community members have wei

Written by Mattt November 28th, 2018 (revised) This article has been translated into: 中文 “You take delight not in a city’s seven or seventy wonders, but in the answer it gives to a question of yours.” Italo Calvino, Invisible Cities Localization (l10n) is the process of adapting your application for a specific market, or locale. Internationalization (i18n) is the process of preparing your app to b

Although iOS 8 and Swift has garnered the lion’s share of attention of the WWDC 2014 announcements, the additions and improvements to testing in Xcode 6 may end up making some of the most profound impact in the long-term. This week, we’ll take a look at XCTest, the testing framework built into Xcode, as well as the exciting new additions in Xcode 6: XCTestExpectation and performance tests. Most Xc

Written by Mattt May 26th, 2014 This article has been translated into: 中文 Civilization is built on infrastructure: roads, bridges, canals, sewers, pipes, wires, fiber. When well thought-out and implemented, infrastructure is a multiplying force that drives growth and development. But when such formative structures are absent or ad hoc, it feels as if progress is made in spite of the situation. It

Simple Collection Operators @count: Returns the number of objects in the collection as an NSNumber. @sum: Converts each object in the collection to a double, computes the sum, and returns the sum as an NSNumber. @avg: Takes the double value of each object in the collection, and returns the average value as an NSNumber. @max: Determines the maximum value using compare:. Objects must support compari

Written by Mattt August 6th, 2012 This article has been translated into: 中文 There are two indicators that tell you everything you need to know about how nice a language is to use: API Consistency Quality of String Implementation NSString is the crown jewel of Foundation. In an age where other languages still struggle to handle Unicode correctly, NSString is especially impressive. Not content to ju

One of the advantages of learning Foundation APIs is that you gain a deeper understanding of the domains that it models. Unless you’re a horologist or ISO 8601 enthusiast, there are probably a few of these components that you’re less familiar with, so let’s take a look at some of the more obscure ones: Era and Year The Gregorian calendar has two eras: BC and AD (alternatively, C.E. and B.C.E). The

Written by Mattt October 21st, 2013 This article has been translated into: 中文 Walk into any American fast food establishment, and you’ll be greeted with a colorful, back-lit display of specials, set menus, and other a la carte items. But as those in-the-know are quick to point out, larger chains often have a secret menu, passed down by oral tradition between line cook workers and patrons over the

Written by Mattt February 4th, 2013 This article has been translated into: 中文 From number stations and numerology to hieroglyphs and hobo codes, there is something truly fascinating about finding meaning that hides in plain sight. Though hidden messages in and of themselves are rarely useful or particularly interesting, it’s the thrill of the hunt that piques our deepest curiosities. It is in this

Written by Mattt October 7th, 2013 This article has been translated into: 中文 Ask anyone who’s been around the NSBlock a few times: Key-Value Observing has the worst API in all of Cocoa. It’s awkward, verbose, and confusing. And worst of all, its terrible API belies one of the most compelling features of the framework. When dealing with complicated, stateful systems, dutiful book-keeping is essenti

Written by Mattt September 23rd, 2013 This article has been translated into: 中文 With the NDA finally lifted, we can finally talk about all of the amazing new APIs in iOS 7. And there are a lot of them. “1500 new APIs”, by Apple’s count during the WWDC Keynote. (Granted, a good portion of that could just be all of the changes from id to instancetype, but that’s a huge number, regardless). We’ll be

Written by Mattt July 29th, 2019 (revised) This article has been translated into: 中文 Product design is about empathy. Knowing what a user wants, what they like, what they dislike, what causes them frustration, and learning to understand and embody those motivations — this is what it takes to make something insanely great. And so we invest in reaching beyond our own operational model of the world.

Written by Mattt August 19th, 2013 This article has been translated into: 中文 NSSet and NSDictionary, along with NSArray are the workhorse collection classes of Foundation. Unlike other standard libraries, implementation details are hidden from developers, allowing them to write simple code and trust that it will be (reasonably) performant. However, even the best abstractions break down; their unde

Written by Mattt August 12th, 2013 This article has been translated into: 中文 What passes for randomness is merely a hidden chain of causality. In a mechanical universe of material interactions expressed through mathematical equations, it is unclear whether nature encodes an element of chance, or if it’s a uniquely human way to reconcile uncertainty. We can be sure of one thing, however: in the clo

Written by Nate Cook & Mattt July 11th, 2018 (revised) This article has been translated into: 中文 Code structure and organization is a matter of pride for developers. Clear and consistent code signifies clear and consistent thought. Even though the compiler lacks a discerning palate when it comes to naming, whitespace, or documentation, it makes all the difference for human collaborators. This week