How to Write Apps with Swift 3: A Comprehensive Guide

Swift, Apple’s powerful programming language, is the driving force behind the creation of applications for macOS and iOS devices. Designed with a singular focus on achieving optimal performance and efficiency, Swift has continually evolved to meet the demands of developers and users. In this guide, we’ll explore the world of Swift 3 and discover what’s new, what’s changed, and how to harness its capabilities for app development.

Swift 3: A Leap Forward

Swift 3 was a significant milestone in the evolution of the Swift language. Introduced at WWDC 2016, it marked a turning point, demonstrating Apple’s commitment to community-driven development. Ted Kremenek, Senior Manager, Languages and Runtimes at Apple, highlighted the importance of this shift, stating, “Swift 3 is the first major update to Swift that is intended to be a product of that community.”

Expanding Beyond iOS and OS X

One of the most notable changes with Swift’s open-sourcing is its expansion beyond the confines of iOS and OS X development. Linux support for Swift has emerged, opening doors for server developers and expanding the language’s horizons. Kremenek emphasized, “We want Swift to be for everybody. This is the first major update since Swift was ported to Linux.”

Evolution of Swift 3

For developers familiar with Swift 2 or earlier versions, Swift 3 brings a host of changes and improvements. The language’s core fundamentals are being honed to provide a solid foundation for future enhancements. Chris Lattner, Sr. Director, Developer Tools Department at Apple, explained, “We want to make the core experience of Swift great.”

Noteworthy Changes in Swift 3

Let’s dive into some of the key changes and features that Swift 3 introduces:

1. Accessing APIs in Swift 3

Accessing Apple APIs is a fundamental aspect of Swift app development. With Swift 3, Apple has overhauled the API language to prioritize clarity. This change aims to enhance the developer experience and streamline the use of Apple’s APIs.

2. Playground Support

Swift 3 offers enhanced support for Playground, making it easier for developers to experiment with the language. You can now download the latest Swift snapshot in Xcode 8 and start coding without the need to restart the development environment.

3. Parameter Labelling

Parameter labelling has undergone significant changes in Swift 3. While Swift 2 aligned closely with Objective-C, the revamped API language calls for parameter labels that are consistent with Swift, simplifying code readability and maintenance.

4. Generics

Generics in Swift 3 have seen a shift in syntax. The signature now takes precedence, with constraints playing a secondary role. This alteration enhances code clarity and makes generics more intuitive to use.

5. Warnings

Swift 3 introduces warnings for unused results in functions, aiding developers in writing cleaner and more efficient code. Developers have the flexibility to override these warnings when necessary.

Features Removed in Swift 3

As Swift 3 progresses, it also entails the removal of certain features:

Currying Function Declaration Syntax: Swift 3 bids farewell to currying function declaration syntax.
‘var’ in Function Parameter Lists: The use of ‘var’ in function parameter lists is no longer supported.
‘++’ and ‘–‘ Operators: The ‘++’ and ‘–‘ operators have been deprecated.
C-style For Loop: The C-style for loop has been phased out in favor of Swift’s modern loop constructs.
Implicit Tuple Splat in Calls: Swift 3 removes implicit tuple splat in function calls.

Ted Kremenek acknowledged that some of these changes might be polarizing or controversial. However, they reflect extensive discussions within the developer community, with transparent logs available online for reference.

Conclusion

Swift 3 represents a significant step forward in the world of app development for macOS and iOS. Its open-source nature, commitment to clarity and efficiency, and the removal of outdated features make it a language poised for the future. As Swift continues to evolve, developers can harness its power to create exceptional applications that run seamlessly on Apple’s ecosystem.