# `GSWritingDirectionValidate`

*Function*

Whether a value contains only recognized writing-direction and kerning-selector bits.

## Declaration

```swift
func GSWritingDirectionValidate(_ value: GSWritingDirection) -> Bool
```

```objc
BOOL GSWritingDirectionValidate(GSWritingDirection value);
```

```python
GSWritingDirectionValidate(value: GSWritingDirection) -> bool
```

## See Also

### Writing Direction

- [`GSWritingDirection`](/Core/GlyphsCore/GSWritingDirection) — The progression of glyphs and lines in text.
- [`GSWritingDirectionValidateOrDefault`](/Core/GlyphsCore/GSWritingDirectionValidateOrDefault) — A value containing only recognized bits, or [`GSWritingDirection.GSWritingDirectionLeftToRight`](/Core/GlyphsCore/GSWritingDirection/GSWritingDirectionLeftToRight) when the value contains an unsupported bit.