Swift is a constantly evolving, general-purpose programming language with a huge community that actively contributes to its features and development. Swift focuses primarily on safety and performance, providing a host of key features to enhance developer productivity and streamline the development of modern, fast, and flexible iOS, iPad, Mac, Apple Watch, and tvOS applications.
What is Swift?
Swift is a general-purpose, multi-paradigm, and cross-platform native programming language for building applications for iOS, iPad, macOS, tvOS, and watchOS. Swift is powerful, fun, and intuitive to work with, offering interactive coding with live feedback, easy debugging, and more! Swift aims to offer a modern way to safely and effectively build performant applications for any of Apple’s platforms.
Swift makes managing and maintaining correctly written applications and programs streamlined and simple. As such, Swift appears quite strict in terms of how code should be written, which requires a structured approach but saves a lot of time and effort in the long run.
Swift is open source under the Apache 2.0 license with a runtime library exception, meaning that end-users don’t need to attribute Swift in their final binary application release. A large and active community contributed extensively to grow and evolve Swift, along with a dedicated core team, bringing frequent updates, bug and vulnerability fixes, and much more.
Swift and Objective-C
Apple released Swift in 2014 at WWDC as an indirect successor to Objective-C. As Apple’s newer native development language, Swift tackled a lot of the shortcomings of Objective-C. It’s easier to read and maintain thanks to a clear, relatively strict, and more human-friendly syntax, leading to less time spent writing code when compared with using Objective-C.
Swift is less prone to runtime errors by catching them earlier, bringing many large, breaking errors to compile time. Interactive coding and debugging make testing and working on code more fun and approachable. Swift introduced Playground for live testing code, with real-time 2D and 3D visualizations, graphs with navigable timelines, graphics, and more.
Swift brought a host of improvements and features that make it significantly different from both Objective-C and C. Despite this, Apple ensured that Swift was interoperable with Objective-C. Applications built on Objective-C didn’t have to be completely rewritten – which was an important consideration Apple held when introducing Swift.
Today, Swift and Objective-C co-exist as many applications used today are written – and therefore need to be maintained – in Objective-C. Swift can be used to add functionality to the current application without having to rebuild it. Most new applications tend to be built with Swift, due to its modern approach to safety, performance, and approachability.
What makes Swift popular?
Swift’s general purpose functionality and modern approach to delivering a fast, easy to use, and flexible development platform led to it being widely adopted. As modern applications have become complex, large, cross-platform, and need to manage varying traffic, Swift’s readable and simplified syntax was appreciated – particularly at the enterprise-level.
As Swift is interoperable with Objective-C, it was favored for new apps, while still providing features for extending existing Objective-C applications. This duality meant that developers weren’t forced to switch over to Swift, giving it time to evolve naturally.
Swift provides extensive features and functions that handle the underlying infrastructure when building applications for iOS, iPad, MacOS, tvOS, and watchOS. This included time-saving and safe features such as automatic memory management, auto code completion, supporting concurrency and asynchronous code, and much more.
Swift’s main features
Many of these features directly addressed issues with existing Objective-C issues. It’s important to remember that Swift is constantly evolving and novel features are being implemented as the Apple ecosystem evolves and developer & business needs change.
Type safe
Swift is a type-safe programming language, requiring developers’ to specify the types of values that the code can work with. This aids safety as you can’t accidentally pass an “Int” value when a “String” is expected.
Optionals
Tied in closely with type-safety, optionals (written as a “?” in Swift) let you pass values as “nil”. Swift uses optionals as a container that holds the value for a type, including the ability to hold no value without returning as an error.
Closures
Closures are self-contained, re-usable, and passable blocks of functional code that help keep Swift code expressive and concise, resulting in less cluttered code that’s easier to read and maintain – especially in large, complex Swift applications.
Automatic memory management
Swift uses ARC (AutoReferenceCounting) to remove the need for a garbage removal feature, making it very different from C-based languages and Objective-C. Swift is memory safe through Swift’s automatically managed memory features.
Supports concurrency and asynchronous code
Swift supports concurrent and parallel programming to delay calling specific parts of the application as long-running operations are computed, while updating other parts such as the UI.
Native error handling
While optionals can be used to avoid errors when a value is “nil”, this is only one of many potential error sources. Swift provides helpful error handling features for both runtime and compile time errors.
Swift offers dozens of other features including tuples, multiple return values, powerful generics, functional programming patterns, quick and concise iteration, and much more. Together, these features make Swift a powerful and structured choice for building cross-platform, safe, and fast applications for the Apple ecosystem.
The Swift Compiler
The Swift compiler is an important part of how Swift works and contributes a lot to Swift improved efficiency and speed. The Swift Compiler is primarily responsible for converting and compiling Swift source code into optimized and executable machine code.
The Swift compiler also offers several front-end tools including IDE integration, syntax coloring, automatic code completion, and more. Here are the main components of the Swift Compiler:
Swift Package Manager
The Swift Package Manager is a cross-platform tool that allows testing, building, and running, which packages Swift libraries and executables. It’s the best way to distribute Swift libraries and source code with the community.
Swift Package Manager allows package configuration while writing in Swift to ease dependency management and configure targets – important aspects of building large and complex enterprise applications.
Swift’s Package Manager is open-source and free to use. It’s downloaded as a Swift package. Package Manager integrates intuitively with the rest of the Swift ecosystem and build system, and handles several important processes automatically, including linking, compiling, and even downloading dependencies to their targets.
Advantages of using Swift for native app development
Swift as a programming language provides several benefits when carefully chosen and applied to the right use case. There is no magic programming language that can do everything. Swift, much like other mobile native programming languages, offers several key advantages. We explore these advantages below and how they impact the development process and potentially the business at large.
Safety
Swift is built around being a structured and type-safe programming language. Variables are initialized before use. Arrays and integers are checked for overflow and any overflow is captured and reported as an error.
Swift handles memory management automatically and offers exclusive access to memory. This reduces coding errors and can speed up the coding process as developers don’t have to manually manage memory allocation, closure, etc.
Swift’s simple syntax is easy to understand, making coding more human friendly, and maintenance easier. This lends to easing API design – along with Swift’s clear API guidelines – and management, helping developers keep the application’s code consistent with the rest of the Swift ecosystem.
Most of the errors in Swift are moved from runtime to compile time, leading to fewer broadly breaking errors and bringing error-handling to an earlier point in the development timeline. Swift is generally viewed as a relatively strict language, which can result in slower coding writing, but saves a lot of time and effort in the long run through enhanced safety and guiding structures/patterns.
Built for performance
Swift’s LLVM compiler is fast compared to Objective-C. Swift makes more efficient use of resources, using modern hardware optimizations. This efficiency extends to Swift’s optimized compilation to machine code, further improving performance and speed.
Swift was originally designed to improve on Objective-C and C, and as such, offers low-level code pieces including types, flow control, and operators. It’s an object oriented programming language with features such as classes, protocols, generics, and more to enhance developer efficiency with Cocoa and Cocoa Touch.
According to Apple, Swift is up to 2.6 times faster than Objective-C, aids in writing quicker code, and provides interactive debugging and testing features to improve overall efficiency and performance.
Interactivity
Playgrounds and REPL (Read Eval Print Loop) are features that Swift offers to harness interactivity. These features are available in X-Code and on iPad for simple and fun coding, with live results from running the code displayed in a side panel. You can use playgrounds to run code and see live visual feedback, graphs, graphs over time, results and other graphics, and more.
A timeline assistant lets developers jump across different time points in a code’s execution to make necessary adjustments, speeding up the code writing process and making experimentation easier.
Using features like Playgrounds, Swift developers can easily test and refine code in a human-friendly, simple, and visual way. This code is easy to export into any Swift project.
Another benefit of Swift’s interactivity is for debugging, The side panel also houses Swift’s LLDB console for debugging. It’s supported in both X-Code and right in the terminal. Objective-C didn’t offer interactivity to the extent that Swift does, making Swift a modern and fun language at any scale.
Community and platform support
The Swift community is large and active, with community contributions being a major determining factor in the direction of the language and its novelty. Swift has a well-defined community structure and makes contributions accessible across the board.
When it comes to platform support, Swift aims to become the best general-purpose programming language in the world. As such, it plans to expand platform support to existing platforms and novel platforms in the future.
Today, Swift supports all Apple platforms, letting you use MacOS to build applications for iOS, macOS, iPad, watchOS, and tvOS. Swift binary builds (designed to allow code distribution that protects intellectual property and offer several other benefits) are supported by X-Code and include important features such as code auto-complete, an integrated debugger, and much more.
Swift is also supported in both Linux and Windows as an open-source programming language for building Swift libraries and applications. Swift aims to be ready to expand their support and eagerly adopt future computing platforms as they emerge.
