# `GSLayer.layerKey`

*Instance Property*

A derived key that distinguishes the layer by its role and attributes.

## Declaration

```swift
var layerKey: String? { get }
```

```objc
@property (nonatomic, readonly) NSString * layerKey;
```

```python
layerKey() -> str
```

## Discussion

Ordinary layers without a name can have no key.

## See Also

### Identity

- [`GSLayer.layerId`](/Core/GlyphsCore/GSLayer/layerId) — The identifier under which the layer is stored in its glyph.
- [`GSLayer resetLayerKey`](/Core/GlyphsCore/GSLayer/resetLayerKey) — Invalidates the derived layer key after information used to form it changes.
- [`GSLayer.layerGroupKey`](/Core/GlyphsCore/GSLayer/layerGroupKey) — A derived key used to group corresponding special and color layers.