Instance MethodFoundationEssentials
transform(updating:body:)
iOS 26.0+
iPadOS 26.0+
Mac Catalyst 26.0+
macOS 26.0+
tvOS 26.0+
visionOS 26.0+
watchOS 26.0+
Tracks the location of the provided ranges throughout the mutation closure, returning a new, updated range that represents the same effective locations after the mutation
mutating func transform<E>(updating ranges: [Range<AttributedString.Index>], body: (inout AttributedString) throws(E) -> Void) throws(E) -> [Range<AttributedString.Index>]? where E : ErrorParameters
rangesRanges to track throughout the
bodyblock.bodyA mutating operation, or set of operations, to perform on this
AttributedString.
Return Value
The updated Ranges that are valid after the mutation has been performed or nil if the mutation performed does not allow for tracking to succeed (such as replacing the provided inout variable with an entirely different AttributedString). When the return value is non-nil, the returned array is guaranteed to be the same size as the provided array with updated ranges at the same indices as their respective original ranges in the input array.