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Swift / String / utf8Span

Contents

Declaration
Return Value
Discussion

utf8Span

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

Declaration

var utf8Span: UTF8Span { get }

Return Value

A UTF8Span over the code units of this string.

Discussion

note:

In the case of bridged UTF-16 string instances (on Apple platforms) this property transcodes the code units the first time it’s called. The transcoded buffer is cached, and subsequent calls can reuse the 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 2026-05-07