{"id":17218778,"url":"https://github.com/nyuichi/leanhol","last_synced_at":"2025-08-25T07:35:07.326Z","repository":{"id":139724265,"uuid":"167488678","full_name":"nyuichi/LeanHOL","owner":"nyuichi","description":"super tiny implementation of higher-order logic proof assistant in lean","archived":false,"fork":false,"pushed_at":"2019-09-29T02:37:22.000Z","size":22,"stargazers_count":21,"open_issues_count":0,"forks_count":0,"subscribers_count":3,"default_branch":"master","last_synced_at":"2025-06-12T15:51:40.171Z","etag":null,"topics":["higher-order-logic","lean","proof-assistant"],"latest_commit_sha":null,"homepage":null,"language":"Lean","has_issues":true,"has_wiki":null,"has_pages":null,"mirror_url":null,"source_name":null,"license":null,"status":null,"scm":"git","pull_requests_enabled":true,"icon_url":"https://github.com/nyuichi.png","metadata":{"files":{"readme":"README.md","changelog":null,"contributing":null,"funding":null,"license":null,"code_of_conduct":null,"threat_model":null,"audit":null,"citation":null,"codeowners":null,"security":null,"support":null,"governance":null,"roadmap":null,"authors":null,"dei":null,"publiccode":null,"codemeta":null}},"created_at":"2019-01-25T05:13:20.000Z","updated_at":"2024-10-12T21:45:52.000Z","dependencies_parsed_at":"2023-04-19T06:45:41.368Z","dependency_job_id":null,"html_url":"https://github.com/nyuichi/LeanHOL","commit_stats":null,"previous_names":[],"tags_count":0,"template":false,"template_full_name":null,"purl":"pkg:github/nyuichi/LeanHOL","repository_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/nyuichi%2FLeanHOL","tags_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/nyuichi%2FLeanHOL/tags","releases_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/nyuichi%2FLeanHOL/releases","manifests_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/nyuichi%2FLeanHOL/manifests","owner_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners/nyuichi","download_url":"https://codeload.github.com/nyuichi/LeanHOL/tar.gz/refs/heads/master","sbom_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/nyuichi%2FLeanHOL/sbom","scorecard":null,"host":{"name":"GitHub","url":"https://github.com","kind":"github","repositories_count":272024803,"owners_count":24860528,"icon_url":"https://github.com/github.png","version":null,"created_at":"2022-05-30T11:31:42.601Z","updated_at":"2022-07-04T15:15:14.044Z","status":"online","status_checked_at":"2025-08-25T02:00:12.092Z","response_time":1107,"last_error":null,"robots_txt_status":"success","robots_txt_updated_at":"2025-07-24T06:49:26.215Z","robots_txt_url":"https://github.com/robots.txt","online":true,"can_crawl_api":true,"host_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub","repositories_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories","repository_names_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repository_names","owners_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners"}},"keywords":["higher-order-logic","lean","proof-assistant"],"created_at":"2024-10-15T03:48:06.836Z","updated_at":"2025-08-25T07:35:07.304Z","avatar_url":"https://github.com/nyuichi.png","language":"Lean","funding_links":[],"categories":[],"sub_categories":[],"readme":"# Super tiny HOL proof assistant in lean\n\nThis material is a proof-of-concept code of my hypothesis that writing a prover will be much easier if I take a proof assistant as its implementation language.\nAn explanatory article about this project will be available soon at techbookfest 2019 spring.\n\nI didn't implement a large part of language features which a proof assistant needs for being called a proof assistant. Instead they are realized by free riding on the metalanguage; I didn't implement:\n\n- parser (it's a DSL)\n- binding structure (use HOAS)\n- type checker (Lean's type checker checks it)\n- type inference (Lean's unifier infers it)\n- (efficient) evaluator (use the NbE technique)\n- tactic language (Lean's tactic language serves it)\n\nThat's why the code is very small (\u003c 300 LoC).\n\nI separate from the main file (`hol.lean`) some codes I additionally wrote to write my article. Mainly looking at `hol.lean` should suffice if you know its technical backgrounds already.","project_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fnyuichi%2Fleanhol","html_url":"https://awesome.ecosyste.ms/projects/github.com%2Fnyuichi%2Fleanhol","lists_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fnyuichi%2Fleanhol/lists"}