Swift is a modern programming language developed by Apple for iOS, macOS, watchOS, and tvOS application development. It combines the flexibility of Objective-C with the performance of C while introducing many new features and improvements to enable developers to build applications more efficiently. Some of the main features of Swift will be introduced in detail below and explained through the corresponding source code.
- Type inference
Swift has a powerful type inference function that can automatically infer the corresponding type based on the initial value of a variable or constant. This makes the code more concise and reduces the redundancy of type declarations. For example, the following code demonstrates the use of type inference:
let message = "Hello, World!" // 推断message为String类型
var count = 10 // 推断count为Int类型
- Optional Types
Swift introduces the concept of optional types to handle situations where a variable or constant may be nil. This helps reduce the occurrence of null pointer exceptions and improves code security. Indicate that the variable or constant is optional by adding a question mark (?) after the type. The following example demonstrates the use of optional types: