# `GSGlyph plainMetricsKey:`

*Instance Method*

The stored glyph-level metrics key for a metric side, or `nil` when none is set.

## Declaration

```swift
func plainMetricsKey(_ side: GSMetricNumbers) -> String?
```

```objc
- (NSString *) plainMetricsKey:(GSMetricNumbers) side;
```

```python
plainMetricsKey_(side: GSMetricNumbers) -> str
```

## Parameters

- `side` — The metric side whose key should be returned.

## Discussion

This does not return a layer-specific override.

## See Also

### Metrics Keys

- [`GSGlyph.leftMetricsKey`](/Core/GlyphsCore/GSGlyph/leftMetricsKey) — Glyph-level metrics key for the left side bearing.
- [`GSGlyph.widthMetricsKey`](/Core/GlyphsCore/GSGlyph/widthMetricsKey) — Glyph-level metrics key for the advance width.
- [`GSGlyph.rightMetricsKey`](/Core/GlyphsCore/GSGlyph/rightMetricsKey) — Glyph-level metrics key for the right side bearing.
- [`GSGlyph.topMetricsKey`](/Core/GlyphsCore/GSGlyph/topMetricsKey) — Glyph-level metrics key for the top side bearing.
- [`GSGlyph.vertOriginMetricsKey`](/Core/GlyphsCore/GSGlyph/vertOriginMetricsKey) — Glyph-level metrics key for the vertical origin.
- [`GSGlyph.vertWidthMetricsKey`](/Core/GlyphsCore/GSGlyph/vertWidthMetricsKey) — Glyph-level metrics key for the vertical advance width.
- [`GSGlyph.bottomMetricsKey`](/Core/GlyphsCore/GSGlyph/bottomMetricsKey) — Glyph-level metrics key for the bottom side bearing.
- [`GSGlyph setPlainMetricsKey:side:`](/Core/GlyphsCore/GSGlyph/setPlainMetricsKey:side:) — Sets the glyph-level metrics key for a metric side.
- [`GSGlyph validateMetricsKey:error:`](/Core/GlyphsCore/GSGlyph/validateMetricsKey:error:) — Validates the syntax of a proposed metrics key.