{
  "title": "Natural Numbers and Addition",
  "origin_url": "https://github.com/standardml/twelf/blob/master/examples/guide/nat.elf",
  "license_guess": null,
  "code_sha256": "f52b2757d2ef66cfeee6ef590951f3c642b7a68328cd755effaa0f6a10330dd4",
  "added_at": "2026-02-08T18:30:00Z"
}