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# Collection Implementations

## Topics

### Instance Properties

[`var endIndex: BlendShapeWeightsSet.Index`](/documentation/RealityKit/BlendShapeWeightsSet/endIndex)

The index of the last entry in a non-empty set.

[`var startIndex: BlendShapeWeightsSet.Index`](/documentation/RealityKit/BlendShapeWeightsSet/startIndex)

The index of the first entry in a non-empty set.

### Instance Methods

[`func index(after: BlendShapeWeightsSet.Index) -> BlendShapeWeightsSet.Index`](/documentation/RealityKit/BlendShapeWeightsSet/index(after:))

Returns the index after the given index.

### Subscripts

[`subscript(BlendShapeWeightsSet.Index) -> BlendShapeWeightsSet.Element`](/documentation/RealityKit/BlendShapeWeightsSet/subscript(_:)-9wfe8)

Accesses the blend shape weights data at the specified index.

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