Swift: The Next-gen Mobile App Programming Language

Developers have always faced a dilemma before choosing the right programming language for a mobile app. To add to this dilemma, there has been a rapid growth in programming languages. Not only have the existing programming languages been modified to provide better versions, but newer programming languages have also come to the fore. The developer thus needs to pick up the right programming language based on the type of app and the kind of features he wants to bring to life. Thus, developers need to keep themselves updated with the pros and cons of all programming languages.

One such new next-gen programming language on the block is Swift, of course, with its latest versions.Swift has become popular amongst developers and is being adopted at a very rapid pace.

When and how was Swift developed?

Apple Inc made the first public release of Swift in 2010. Chris Lattner, head of Apples developer tools department, took almost four years to come up with the first official version of Swift. Later, however, it was supported by many other contributors. They have taken ideas from many other popular languages such as Objective-C, C#, Python, Rust, Haskell, Ruby, and CLU. Thus, finally, Swift was first introduced at Apple’s 2014 Worldwide Developers Conference (WWDC) with the Gold Master of Xcode 6.

What platforms are most compatible with apps built with Swift?

iOS devices dating back to iOS 7 or later, and OS X devices dating back to OS X 10.9 or later, are most compatible with apps built with Swift. All versions of watchOS and tvOS also have support for running Swift-built apps.

Why Swift?

A wide range of enterprises, especially businesses that have invested in Apple’s platforms or developed their own B2B/enterprise apps have switched to Swift because of the following reasons:

• Better type safety, security, and performance
• Has a wide range of effects for developing iOS, OS X, watchOS, tvOS apps, and many other platforms (like Linux) apps much faster and with fewer bugs and crashes than ever before
• Enhanced readability and lesser coding
• Easy programming language to learn, so even students, entry-level developers, and long-standing Mac and iOS developers, can focus their development skills on Swift
• Open source
• Available for developing on platforms other than Apple
• Easy cross-platform app development
• Easy to keep apps up to date
• Swift playgrounds provide interactive coding
• Scope for further improvement

How Swift differs from Objective-C?

Though Apple is still updating Objective C language, Swift is rapidly overtaking it and becoming more popular on Apples platforms. Here are a few main differences between Objective-C and Swift.

• Goodbye header files: Header files are used in Objective-C to declare its functions and definitions publically. However, Swift makes it easier for developers by allowing them to write a single .swift file that contains typical header information, properties, and all of the class defines in a single file.
• Hello REPL: Though Objective-C and Swift are both compiled languages, Swift has a REPL (Read-Eval-Print Loop). This REPL is used for testing and typically supports only interpreted languages. However, in case of Swift, the REPL is available in the command line and Xcode and is known as Playground. This Playground allows developers to write Swift code and evaluates it immediately to print out the results in the sidebar. Opening Xcode can create a new Swift Playground in Xcode and selecting File | New | Playground. A new window appears, and another Swift code can be tested. Thus, Playgrounds help to evaluate and test a code prior to creating an entire iOS or OS X project.
• Stronger Type inference: In case of both Objective-C and Swift, object types are strongly typed. This means that the compiler needs exact information about the type of object (string, array, dictionary, custom object, etc.) that needs to be stored in memory for a particular variable. However, Swift has strong types that allow the compiler to infer the type automatically based on the objects that have been assigned to a variable.

What are the different versions of Swift developed later?

Swift 2.0

With many new added features and refinements, Apple released Swift 2.0 at WWDC 15 with the Xcode 7 Gold Master build. Some of the new features in Swift 2.0 are:

• It targets older versions of iOS and OS X.
• New Linux port made available in the open source Swift.
• New error handling model that uses try, throw and catch keywords.
• It is safer, with the #available block that wraps lines of code that need to be executed on systems where the framework is available.
• Software development kits (SDKs) became Swift-ier as generics, and nullability was added to the existing Objective-C frameworks to improve the interface with Swift code.

Swift 3.0

Apple released Swift 3.0 at WWDC 16 with the release of Xcode 8.. The new features in Swift 3.0 include:

• The core language and standard library refined to purge the language of NS prefixes and other Objective-C holdovers
• Major additions to the Linux port of Swift
• Swift Package Manager added to make it easier to manage dependencies

Swift 4.0

Swift 4.0 was released at WWDC 17 in beta form to developers alongside Xcode 9. Overcoming the constraints of C compatibility, Swift 4 embraces the best of C and Objective-C. A few refinements and features added to this release of Swift include:

• Safe programming patterns
• Modern programming features
• Objective-C like syntax and new codeable protocol that allows for easy serialization of data wrapped instructs
• Strings received a major overhaul, making them collections of characters
• String literals can now break into multiple lines using the new \"\"\" declaration (three sets of quote marks) to open and close the multiline string
• Programs run on many existing iOS 6 and OS X 10.8 platforms as it uses the same runtime as the current Obj-C system on Mac OS and iOS.
• Seamless access to existing Cocoa frameworks
• Integrates the procedural and object-oriented portions of the language
• Does not need a separate library import to support functionalities like input/output or string handling
• Playground feature that helps write the code and execute it to see the results immediately

These features indicate that Swift has revolutionized the app development process thus becoming the next-gen Programming Language.