# `GSGlyph collectBraceLayerIDsMasters:allKeys:`

*Instance Method*

The font masters including representations of active Intermediate-layer locations.

## Declaration

```swift
func collectBraceLayerIDsMasters(_ masters: [GSFontMaster], allKeys: NSOrderedSet) -> [GSFontMaster]?
```

```objc
- (NSArray<GSFontMaster *> *) collectBraceLayerIDsMasters:(NSArray<GSFontMaster *> *) masters allKeys:(NSOrderedSet<NSString *> *) allKeys;
```

```python
collectBraceLayerIDsMasters_allKeys_(masters: list[GSFontMaster], allKeys: NSOrderedSet<NSString *>) -> list[GSFontMaster]
```

## Parameters

- `masters` — The original font masters.
- `allKeys` — The layer and font master identifiers to inspect.

## Discussion

This allows instance interpolation to account for Intermediate-layer locations. Returns `nil` when no qualifying Intermediate layer is found.

## See Also

### Layer Groups

- [`GSGlyph layerGroups`](/Core/GlyphsCore/GSGlyph/layerGroups) — The layer identifier groups used to check compatibility and coordinate edits across corresponding layers.
- [`GSGlyph layerGroupsInstances:masters:ignoreEmptyLayers:error:`](/Core/GlyphsCore/GSGlyph/layerGroupsInstances:masters:ignoreEmptyLayers:error:) — The layer identifier groups required by a set of instances.
- [`GSGlyph forcedLayerGroupIdsSeenLayers:ignoreEmptyLayers:`](/Core/GlyphsCore/GSGlyph/forcedLayerGroupIdsSeenLayers:ignoreEmptyLayers:) — The layer identifier groups formed without reference to configured instances.
- [`GSGlyph layerGroupIDSetForLayer:`](/Core/GlyphsCore/GSGlyph/layerGroupIDSetForLayer:) — The forced layer group containing a layer, or `nil` when the layer is not in a group.
- [`GSGlyph layerGroupIDSetForLayer:ignoreEmptyLayers:`](/Core/GlyphsCore/GSGlyph/layerGroupIDSetForLayer:ignoreEmptyLayers:) — The forced layer group containing a layer, or `nil` when the layer is not in a group.
- [`GSGlyph layerGroupIDsForLayer:`](/Core/GlyphsCore/GSGlyph/layerGroupIDsForLayer:) — The forced layer group containing a layer as an array, or `nil` when the layer is not in a group.
- [`GSGlyph compatibleLayerGroupIdsForLayer:`](/Core/GlyphsCore/GSGlyph/compatibleLayerGroupIdsForLayer:) — The identifiers of layers in the same group that have compatible shapes, anchors, and path-component hints.