# `GSFont addNumber:`

*Instance Method*

Adds a number definition to the font.

## Declaration

```swift
func addNumber(_ number: GSMetric)
```

```objc
- (void) addNumber:(GSMetric *) number;
```

```python
addNumber_(number: GSMetric)
```

## Discussion

Missing number identifiers are created automatically.

## See Also

### Numbers

- [`GSFont.numbers`](/Core/GlyphsCore/GSFont/numbers) — Font-wide number definitions.
- [`GSFont countOfNumbers`](/Core/GlyphsCore/GSFont/countOfNumbers) — Returns the number of number definitions.
- [`GSFont objectInNumbersAtIndex:`](/Core/GlyphsCore/GSFont/objectInNumbersAtIndex:) — Returns the number definition at an index.
- [`GSFont numberForId:`](/Core/GlyphsCore/GSFont/numberForId:) — Returns the first number definition with an identifier.
- [`GSFont numberForName:`](/Core/GlyphsCore/GSFont/numberForName:) — Returns the first number definition with a name.
- [`GSFont removeObjectFromNumbers:`](/Core/GlyphsCore/GSFont/removeObjectFromNumbers:) — Removes a number definition from the font.