Introduction to Swift apple's programming language

Swift is a new programming language for writing iOS and OS X applications. Swift combines the benefits of C and Objective-C and is not limited by C compatibility. Swift USES secure programming mode and adds many new features that make programming easier, more extensible, and more fun. Swift supports the Cocoa and Cocoa Touch frameworks.

The development of Swift began a long time ago. To lay the groundwork for Swift, apple improved the compiler, debugger, and framework structure to make Swift use automatic reference counting (Automatic Reference Counting, ARC) to simplify memory management.

Objective-C developers are no strangers to Swift. It takes the named parameters of Objective-C and dynamic object model, seamlessly connects to the existing Cocoa framework, and is compatible with the Objective-C code. On top of that, Swift has many new features that support both procedural and object-oriented programming.

Swift is also easy for beginners. Swift is a programming language that meets industry standards and is as expressive and fun as a scripting language. Swift supports code preview, a revolutionary feature that allows programmers to run Swift code without compiling and running the application and see the results in real time.

Swift combines the best of modern programming languages with the wisdom of apple's engineer culture. The compiler optimizes performance and the programming language optimizes development, both of which don't interfere with each other. Swift can be used to develop "hello, world" such small programs, can also be used to develop a complete operating system. All of these features make Swift a worthwhile investment for developers and for apple.

Writing iOS and OS X applications in Swift will be a great experience, and Swift will continue to develop new features and compatibility.

Swift provides all basic data types for C and Objective-C, including the integer Int, floating point Double, Float, Boolean Bool, and String strings. Swift also provides two powerful collection data types, Array (array) and Dictionary (dictionary).

Like C1, Swift USES variables to store and access values. Swift also supports variables whose values cannot be changed, which in C we call constants, but in Swift constants are much more powerful. Constants can be used when the value of a variable does not need to be changed, which makes the code safer and cleaner.

In addition, Swift introduces some advanced data types that are not available in Objective-C, such as tuples (tuples), which allows you to create and pass a set of values.

Swift also introduces optional types (Optionals) to handle situations where variable values do not exist. Optional means two things: 1 is that the variable exists, for example, is equal to X, and 2 is that the variable value does not exist at all. Optionals is similar to the Objective-C pointer to nil, but works for all data types, not just classes. Optionals is more secure and concise than the nil pointer in Objective-C, and is at the heart of many of Swift's most powerful features.

Swift is a type safe language. Optionals is the representative. Swift helps you work in a type-safe environment. If you need to use String types in your code, Swift's security mechanism prevents you from mistakenly passing Int values, which allows you to detect and fix problems during development.