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Swift / String / String.UTF8View / span

Contents

Declaration
Return Value
Discussion

span

A span over the UTF-8 code units that make up this string.

Declaration

var span: Span<UTF8.CodeUnit> { get }

Return Value

A Span over the UTF-8 code units of this String.

Discussion

note:

On Apple platforms, this property transcodes the code units of bridged UTF-16 String instances on first access and caches the result. Subsequent calls can reuse the cached buffer.

note:

O(1) for native UTF-8 strings, amortized O(1) for bridged UTF-16 strings.

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SwiftInstance Property

iOS 26.0+iPadOS 26.0+Mac Catalyst 26.0+macOS 26.0+tvOS 26.0+visionOS 26.0+watchOS 26.0+

Declaration
Return Value
Discussion

Built on 2026-08-05 · Snapshot snapshot-20260805-beta.2 (macOS 27.0) · Commit 4bc0d8f · by @g-cqd · based on Apple Developer Documentation