.swift File — Swift Source Code

Swift is a modern, compiled programming language developed by Apple, introduced in 2014 as the successor to Objective-C for iOS, macOS, watchOS, and tvOS development. SWIFT files contain source code in a language designed for safety, performance, and expressiveness, featuring strong typing with type inference, optionals for null safety, value types (structs and enums), protocol-oriented programming, automatic reference counting, generics, and pattern matching. Swift eliminates entire categories of common bugs through its design — optional types prevent null pointer exceptions, and memory safety is enforced by the compiler. The language supports both functional and object-oriented paradigms and interoperates with Objective-C and C code. Swift is the primary language for all Apple platform development, used in millions of iOS apps. Beyond Apple platforms, Swift is also used for server-side development (Vapor, Kitura) and has been open-sourced with Linux support. Swift Playgrounds provides an interactive learning environment. The language evolves through the Swift Evolution process, with recent versions adding concurrency (async/await, actors), result builders, and property wrappers.