---
license: apache-2.0
library_name: resyn
pipeline_tag: text-classification
tags:
- regex
- regex-synthesis
- program-synthesis
- pytorch
- model_hub_mixin
- pytorch_model_hub_mixin
- router
datasets:
- mrseongminkim/ReSyn
---

# ReSyn — Router

This repository contains the pre-trained **Router** model presented in the paper [ReSyn: A Generalized Recursive Regular Expression Synthesis Framework](https://huggingface.co/papers/2603.24624).

ReSyn is a synthesizer-agnostic divide-and-conquer framework that decomposes complex regular expression synthesis problems into manageable sub-problems by adaptively predicting whether to split examples sequentially (Concatenation) or group them by structural similarity (Union).

**Router** decides *how* to decompose a synthesis problem. Given a set of positive example strings, it classifies the set into one of three actions — **Concat**, **Union**, or **No-Op** — telling the framework whether to split the examples sequentially, group them by structural similarity, or synthesize them directly without further decomposition.

## Links

- **Paper:** [ReSyn: A Generalized Recursive Regular Expression Synthesis Framework](https://huggingface.co/papers/2603.24624)
- **GitHub Repository:** [mrseongminkim/ReSyn](https://github.com/mrseongminkim/ReSyn)
- **Dataset:** [mrseongminkim/ReSyn](https://huggingface.co/datasets/mrseongminkim/ReSyn)

## Usage

These are custom PyTorch models that use [`PyTorchModelHubMixin`](https://huggingface.co/docs/huggingface_hub/package_reference/mixins#huggingface_hub.PyTorchModelHubMixin). The model class is defined in the [GitHub repository](https://github.com/mrseongminkim/ReSyn); clone it first so that the `ReSyn` package is importable, then:

```python
from ReSyn.model import Router

model = Router.from_pretrained("mrseongminkim/ReSyn-Router").eval()
```

See [`ReSyn/server.py`](https://github.com/mrseongminkim/ReSyn/blob/main/ReSyn/server.py) for the full input encoding / output decoding used at inference time.

## Citation

If you find this work useful, please cite:

```bibtex
@inproceedings{kim2026resyn,
  title={ReSyn: A Generalized Recursive Regular Expression Synthesis Framework},
  author={Kim, Seongmin and Cheon, Hyunjoon and Kim, Su-Hyeon and Han, Yo-Sub and Ko, Sang-Ki},
  booktitle={Proceedings of the Thirty-Fifth International Joint Conference on Artificial Intelligence (IJCAI-26)},
  year={2026}
}
```