{"id":26518753,"url":"https://github.com/httpie/fractional-indexing-python","last_synced_at":"2025-03-21T10:02:09.314Z","repository":{"id":57432103,"uuid":"462072728","full_name":"httpie/fractional-indexing-python","owner":"httpie","description":"Fractional Indexing in Python","archived":false,"fork":false,"pushed_at":"2024-04-19T11:26:01.000Z","size":49,"stargazers_count":29,"open_issues_count":1,"forks_count":5,"subscribers_count":2,"default_branch":"main","last_synced_at":"2025-03-16T01:53:55.184Z","etag":null,"topics":[],"latest_commit_sha":null,"homepage":"https://pypi.org/project/fractional-indexing","language":"Python","has_issues":true,"has_wiki":null,"has_pages":null,"mirror_url":null,"source_name":null,"license":"cc0-1.0","status":null,"scm":"git","pull_requests_enabled":true,"icon_url":"https://github.com/httpie.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}},"created_at":"2022-02-22T00:02:19.000Z","updated_at":"2025-02-27T19:56:32.000Z","dependencies_parsed_at":"2022-08-30T11:41:04.055Z","dependency_job_id":null,"html_url":"https://github.com/httpie/fractional-indexing-python","commit_stats":null,"previous_names":[],"tags_count":2,"template":false,"template_full_name":null,"repository_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/httpie%2Ffractional-indexing-python","tags_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/httpie%2Ffractional-indexing-python/tags","releases_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/httpie%2Ffractional-indexing-python/releases","manifests_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/httpie%2Ffractional-indexing-python/manifests","owner_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners/httpie","download_url":"https://codeload.github.com/httpie/fractional-indexing-python/tar.gz/refs/heads/main","host":{"name":"GitHub","url":"https://github.com","kind":"github","repositories_count":244776322,"owners_count":20508506,"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","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":[],"created_at":"2025-03-21T10:02:08.617Z","updated_at":"2025-03-21T10:02:09.294Z","avatar_url":"https://github.com/httpie.png","language":"Python","readme":"# Fractional Indexing\n\nThis is based on [Implementing Fractional Indexing\n](https://observablehq.com/@dgreensp/implementing-fractional-indexing) by [David Greenspan\n](https://github.com/dgreensp).\n\nFractional indexing is a technique to create an ordering that can be used\nfor [Realtime Editing of Ordered Sequences](https://www.figma.com/blog/realtime-editing-of-ordered-sequences/).\n\nThis implementation includes variable-length integers, and the prepend/append optimization described in David's article.\n\n## Installation\n\n```bash\n$ pip install fractional-indexing\n```\n\n## Usage\n\n### Generate a single key\n\n```python\nfrom fractional_indexing import generate_key_between\n\n\n# Insert at the beginning\nfirst = generate_key_between(None, None)\nassert first == 'a0'\n\n# Insert after 1st\nsecond = generate_key_between(first, None)\nassert second == 'a1'\n\n# Insert after 2nd\nthird = generate_key_between(second, None)\nassert third == 'a2'\n\n# Insert before 1st\nzeroth = generate_key_between(None, first)\nassert zeroth == 'Zz'\n\n# Insert in between 2nd and 3rd (midpoint)\nsecond_and_half = generate_key_between(second, third)\nassert second_and_half == 'a1V'\n\n```\n\n### Generate multiple keys\n\nUse this when generating multiple keys at some known position, as it spaces out indexes more evenly and leads to shorter keys.\n\n```python\nfrom fractional_indexing import generate_n_keys_between\n\n\n# Insert 3 at the beginning\nkeys = generate_n_keys_between(None, None, n=3)\nassert keys == ['a0', 'a1', 'a2']\n\n# Insert 3 after 1st\nkeys = generate_n_keys_between('a0', None, n=3)\nassert keys == ['a1', 'a2', 'a3']\n\n# Insert 3 before 1st\nkeys = generate_n_keys_between(None, 'a0', n=3)\nassert keys == ['Zx', 'Zy', 'Zz']\n\n# Insert 3 in between 2nd and 3rd (midpoint)\nkeys = generate_n_keys_between('a1', 'a2', n=3)\nassert keys == ['a1G', 'a1V', 'a1l']\n\n```\n\n### Validate a key\n\n```python\nfrom fractional_indexing import validate_order_key, FIError\n\n\nvalidate_order_key('a0')\n\ntry:\n    validate_order_key('foo')\nexcept FIError as e:\n    print(e)  # fractional_indexing.FIError: invalid order key: foo\n\n```\n\n### Use custom base digits\n\nBy default, this library uses Base62 character encoding. To use a different set of digits, pass them in as the `digits`\nargument to `generate_key_between()`, `generate_n_keys_between()`, and `validate_order_key()`:\n\n```python\nfrom fractional_indexing import generate_key_between, generate_n_keys_between, validate_order_key\n\n\nBASE_95_DIGITS = ' !\"#$%\u0026\\'()*+,-./0123456789:;\u003c=\u003e?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\\\]^_`abcdefghijklmnopqrstuvwxyz{|}~'\n\nassert generate_key_between(None, None, digits=BASE_95_DIGITS) == 'a '\nassert generate_key_between('a ', None, digits=BASE_95_DIGITS) == 'a!'\nassert generate_key_between(None, 'a ', digits=BASE_95_DIGITS) == 'Z~'\n\nassert generate_n_keys_between('a ', 'a!', n=3, digits=BASE_95_DIGITS) == ['a\"', 'a#', 'a$']\n\nvalidate_order_key('a ', digits=BASE_95_DIGITS)\n\n```\n\n## Other Languages\n\nThis is a Python port of the original JavaScript implementation by [@rocicorp](https://github.com/rocicorp). That means\nthat this implementation is byte-for-byte compatible with:\n\n| Language   | Repo                                                  |\n|------------|-------------------------------------------------------|\n| JavaScript | https://github.com/rocicorp/fractional-indexing       |\n| Go         | https://github.com/rocicorp/fracdex                   |\n| Kotlin     | https://github.com/darvelo/fractional-indexing-kotlin |\n| Ruby       | https://github.com/kazu-2020/fractional_indexer       |\n","funding_links":[],"categories":["Python"],"sub_categories":[],"project_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fhttpie%2Ffractional-indexing-python","html_url":"https://awesome.ecosyste.ms/projects/github.com%2Fhttpie%2Ffractional-indexing-python","lists_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fhttpie%2Ffractional-indexing-python/lists"}