# `GSFont feaBlockForFileName:`

*Instance Method*

Returns the FEA block (feature, class, prefix) matching the given file name.

## Declaration

```swift
func feaBlock(forFileName fileName: String) -> GSFeaBlock?
```

```objc
- (GSFeaBlock *) feaBlockForFileName:(NSString *) fileName;
```

```python
feaBlockForFileName_(fileName: str) -> GSFeaBlock
```

## Discussion

A matching block is resolved from the file path stored in the block, or from the title derived from the file name.

## See Also

### Layout Code

- [`GSFont addFeaBlockForFileName:code:`](/Core/GlyphsCore/GSFont/addFeaBlockForFileName:code:) — Adds a feature block to the font, basing the type and title on the file name.
- [`GSFont languagesWithLayoutRules`](/Core/GlyphsCore/GSFont/languagesWithLayoutRules) — Script and language tags that have layout rules in the compiled temporary font.