# `GSLayer metricsValueAndHeight(_:forKey:)`

*Instance Method*

Value and height described by a metrics key for a metric side, or `nil` when the key cannot be resolved.

## Declaration

```swift
func metricsValueAndHeight(_ metric: GSMetricNumbers, forKey key: String) -> (value: CGFloat, height: Int)?
```

## See Also

### Metric Values

- [`GSMetricNumbers`](/Core/GlyphsCore/GSMetricNumbers)
- [`GSLayer metricsValue:atHeight:`](/Core/GlyphsCore/GSLayer/metricsValue:atHeight:) — Metric value for a side at a measurement height.
- [`GSLayer metricsValue(_:forKey:)`](/Core/GlyphsCore/GSLayer/metricsValue(_:forKey:)) — Value described by a metrics key for a metric side, or `nil` when the key cannot be resolved.