---
title: "index(before:)"
framework: realitykit
role: symbol
role_heading: Instance Method
path: "realitykit/blendshapeweights/index(before:)"
---

# index(before:)

Returns the position in the sequence of the weight that preceeds the given position.

## Declaration

```swift
func index(before i: BlendShapeWeights.Index) -> BlendShapeWeights.Index
```

## Discussion

Discussion For more on calculating indices, see index(before:).