Swift6の新機能は?
Asked on 2025-06-12
•@wwdc251 search
Swift 6 introduces several new features and improvements aimed at enhancing performance, safety, and ease of use. Here are some of the key updates:
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Background Indexing: Enabled by default for SwiftPM projects in VS Code and other IDEs, improving editor features like Jump to Definition and code completion results.
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Inline Arrays: Allows declaration of arrays with a fixed size that can be stored on the stack, enhancing performance by avoiding heap memory usage.
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New Span Type: Provides a safe alternative to pointers for fast, direct access to contiguous memory, improving interoperability with languages like C.
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Strict Memory Safety: A new mode that requires explicit acknowledgment of unsafe API usage in source code, enhancing security.
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Concurrency Improvements: Swift 6.2 makes concurrency more approachable by defaulting to single-threaded execution until concurrency is explicitly introduced, reducing data race risks.
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Embedded Swift: Expanded support for writing code targeting constrained environments like firmware for embedded devices.
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Development Workflow Enhancements: Improvements in writing, building, and debugging code, particularly in VS Code with the Swift extension.
For more detailed information, you can refer to the session What’s new in Swift (00:00:00).

What’s new in Swift
Join us for an update on Swift. We’ll talk about workflow improvements that make you more productive, and new and modernized library APIs for fundamental programming tasks. We’ll show examples of Swift adoption throughout more layers of the software stack. Finally, we’ll explore new language features for both improving approachability of concurrency, and achieving peak performance when you need it.

Platforms State of the Union
Discover the newest advancements on Apple platforms.

Explore concurrency in SwiftUI
Discover how SwiftUI leverages Swift concurrency to build safe and responsive apps. Explore how SwiftUI uses the main actor by default and offloads work to other actors. Learn how to interpret concurrency annotations and manage async tasks with SwiftUI’s event loop for smooth animations and UI updates. You’ll leave knowing how to avoid data races and write code fearlessly.