# StringDistance

> **Class** in `langchain_classic`

📖 [View in docs](https://reference.langchain.com/python/langchain-classic/smith/evaluation/config/RunEvalConfig/StringDistance)

Configuration for a string distance evaluator.

## Signature

```python
StringDistance()
```

## Extends

- `SingleKeyEvalConfig`

## Properties

- `evaluator_type`
- `distance`
- `normalize_score`

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[View source on GitHub](https://github.com/langchain-ai/langchain/blob/02991cb4cf2063d51a07268edafb05fe53de1826/libs/langchain/langchain_classic/smith/evaluation/config.py#L163)