# replaceInfluenceJointIndices(_:) Fills the influence joint index buffer using the given closure. /// After the closure returns, the framework validates every index. An out-of-range index causes a throw. ``` func replaceInfluenceJointIndices(_ body: @_lifetime(0: copy 0) (inout MutableRawSpan) -> R) throws -> R where R : ~Copyable ``` ## Parameters `body` A closure that receives a mutable span over the buffer. ## Return Value The value returned by `body`. ## Discussion> Throws: If any index is outside `[0, skinning.jointTransformCount)`. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)