{"id":16964998,"url":"https://github.com/propensive/feudalism","last_synced_at":"2025-04-11T23:05:22.082Z","repository":{"id":210040583,"uuid":"725569340","full_name":"propensive/feudalism","owner":"propensive","description":"Controlled borrowing of mutable values for safe concurrency","archived":false,"fork":false,"pushed_at":"2025-01-26T12:13:46.000Z","size":1382,"stargazers_count":2,"open_issues_count":0,"forks_count":0,"subscribers_count":2,"default_branch":"main","last_synced_at":"2025-04-11T23:04:47.797Z","etag":null,"topics":["mutexes","scala"],"latest_commit_sha":null,"homepage":"https://soundness.dev/feudalism/","language":"Scala","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/propensive.png","metadata":{"files":{"readme":".github/readme.md","changelog":null,"contributing":".github/contributing.md","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":"2023-11-30T12:24:43.000Z","updated_at":"2025-01-26T12:13:49.000Z","dependencies_parsed_at":"2024-02-01T08:28:05.671Z","dependency_job_id":"a21010af-f650-4e6b-aa19-a52789c45222","html_url":"https://github.com/propensive/feudalism","commit_stats":null,"previous_names":["propensive/feudalism"],"tags_count":19,"template":false,"template_full_name":null,"repository_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/propensive%2Ffeudalism","tags_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/propensive%2Ffeudalism/tags","releases_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/propensive%2Ffeudalism/releases","manifests_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/propensive%2Ffeudalism/manifests","owner_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners/propensive","download_url":"https://codeload.github.com/propensive/feudalism/tar.gz/refs/heads/main","host":{"name":"GitHub","url":"https://github.com","kind":"github","repositories_count":248492871,"owners_count":21113163,"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":["mutexes","scala"],"created_at":"2024-10-13T23:44:48.498Z","updated_at":"2025-04-11T23:05:22.053Z","avatar_url":"https://github.com/propensive.png","language":"Scala","funding_links":[],"categories":[],"sub_categories":[],"readme":"[\u003cimg alt=\"GitHub Workflow\" src=\"https://img.shields.io/github/actions/workflow/status/propensive/feudalism/main.yml?style=for-the-badge\" height=\"24\"\u003e](https://github.com/propensive/feudalism/actions)\n[\u003cimg src=\"https://img.shields.io/discord/633198088311537684?color=8899f7\u0026label=DISCORD\u0026style=for-the-badge\" height=\"24\"\u003e](https://discord.com/invite/MBUrkTgMnA)\n\u003cimg src=\"/doc/images/github.png\" valign=\"middle\"\u003e\n\n# Feudalism\n\n__Controlled borrowing of mutable values for safe concurrency.__\n\nA _mutex_ is a data structure designed for safe reading and writing to a\nmutable variable in a concurrent environment. Specifically, a mutex variable\nmay be mutated (that is, its old value read and transformed into a new value)\nso long as no other threads are reading or writing to the mutex at the same\ntime. However, any number of threads may read the mutex variable concurrently.\n\nFeudalism implements a generic `Mutex` type which guarantees these constraints.\n\n## Features\n\n- implements a basic, generic mutex\n- provides fast and safe concurrent access to a variable\n- especially performant on Java 21 with virtual threads\n\n\n## Availability\n\n\n\n\n\n\n\n## Getting Started\n\n### Creating a new Mutex\n\nA new mutex, an instance of type `Mutex[ValueType]` for some choice of\n`ValueTyp`, can be constructed by supplying its initial value to the `Mutex`\nfactory method, like so:\n```scala\nval count: Mutex[Int] = Mutex(32)\n```\n\nThis represents a mutex variable, which is set to `32`. Any thread which has a\nreference to `count` may read or modify this variable, but only in delimited\nblocks.\n\nWe can read the value only through a lambda applied to the `read` method of\n`Mutex`, which provides a reference for accessing the value.\n\n\n\n## Status\n\nFeudalism is classified as __fledgling__. For reference, Soundness projects are\ncategorized into one of the following five stability levels:\n\n- _embryonic_: for experimental or demonstrative purposes only, without any guarantees of longevity\n- _fledgling_: of proven utility, seeking contributions, but liable to significant redesigns\n- _maturescent_: major design decisions broady settled, seeking probatory adoption and refinement\n- _dependable_: production-ready, subject to controlled ongoing maintenance and enhancement; tagged as version `1.0.0` or later\n- _adamantine_: proven, reliable and production-ready, with no further breaking changes ever anticipated\n\nProjects at any stability level, even _embryonic_ projects, can still be used,\nas long as caution is taken to avoid a mismatch between the project's stability\nlevel and the required stability and maintainability of your own project.\n\nFeudalism is designed to be _small_. Its entire source code currently consists\nof 109 lines of code.\n\n## Building\n\nFeudalism will ultimately be built by Fury, when it is published. In the\nmeantime, two possibilities are offered, however they are acknowledged to be\nfragile, inadequately tested, and unsuitable for anything more than\nexperimentation. They are provided only for the necessity of providing _some_\nanswer to the question, \"how can I try Feudalism?\".\n\n1. *Copy the sources into your own project*\n   \n   Read the `fury` file in the repository root to understand Feudalism's build\n   structure, dependencies and source location; the file format should be short\n   and quite intuitive. Copy the sources into a source directory in your own\n   project, then repeat (recursively) for each of the dependencies.\n\n   The sources are compiled against the latest nightly release of Scala 3.\n   There should be no problem to compile the project together with all of its\n   dependencies in a single compilation.\n\n2. *Build with [Wrath](https://github.com/propensive/wrath/)*\n\n   Wrath is a bootstrapping script for building Feudalism and other projects in\n   the absence of a fully-featured build tool. It is designed to read the `fury`\n   file in the project directory, and produce a collection of JAR files which can\n   be added to a classpath, by compiling the project and all of its dependencies,\n   including the Scala compiler itself.\n   \n   Download the latest version of\n   [`wrath`](https://github.com/propensive/wrath/releases/latest), make it\n   executable, and add it to your path, for example by copying it to\n   `/usr/local/bin/`.\n\n   Clone this repository inside an empty directory, so that the build can\n   safely make clones of repositories it depends on as _peers_ of `feudalism`.\n   Run `wrath -F` in the repository root. This will download and compile the\n   latest version of Scala, as well as all of Feudalism's dependencies.\n\n   If the build was successful, the compiled JAR files can be found in the\n   `.wrath/dist` directory.\n\n## Contributing\n\nContributors to Feudalism are welcome and encouraged. New contributors may like\nto look for issues marked\n[beginner](https://github.com/propensive/feudalism/labels/beginner).\n\nWe suggest that all contributors read the [Contributing\nGuide](/contributing.md) to make the process of contributing to Feudalism\neasier.\n\nPlease __do not__ contact project maintainers privately with questions unless\nthere is a good reason to keep them private. While it can be tempting to\nrepsond to such questions, private answers cannot be shared with a wider\naudience, and it can result in duplication of effort.\n\n## Author\n\nFeudalism was designed and developed by Jon Pretty, and commercial support and\ntraining on all aspects of Scala 3 is available from [Propensive\nO\u0026Uuml;](https://propensive.com/).\n\n\n\n## Name\n\n_Feudalism_ was the predominant social system in Medieval times, whereby\nwealthy landowners would divide their land into strips, and lease it to tenants\nto work. This is vaguely analogous, on some level, to the controlled access a\nmutex provides to readers and writers of its variable.\n\nIn general, Soundness project names are always chosen with some rationale,\nhowever it is usually frivolous. Each name is chosen for more for its\n_uniqueness_ and _intrigue_ than its concision or catchiness, and there is no\nbias towards names with positive or \"nice\" meanings—since many of the libraries\nperform some quite unpleasant tasks.\n\nNames should be English words, though many are obscure or archaic, and it\nshould be noted how willingly English adopts foreign words. Names are generally\nof Greek or Latin origin, and have often arrived in English via a romance\nlanguage.\n\n## Logo\n\nThe logo shows a ring, split into two halves representing read-access and\nwrite-access; in the read-access half, the ring splits into multiple threads,\nwhile in the write-access half, the ring is just a single thread.\n\n## License\n\nFeudalism is copyright \u0026copy; 2025 Jon Pretty \u0026 Propensive O\u0026Uuml;, and\nis made available under the [Apache 2.0 License](/license.md).\n\n","project_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fpropensive%2Ffeudalism","html_url":"https://awesome.ecosyste.ms/projects/github.com%2Fpropensive%2Ffeudalism","lists_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fpropensive%2Ffeudalism/lists"}