unison README

The project's README from github.com/unisonweb/unison. As one markdown file: README.md.

The Unison language

CI Status Pre-Release Status

Alt

Overview

Unison is a statically-typed functional language with type inference, an effect system, and advanced tooling. It is based around a big idea of content-addressed code, in which function are identified by a hash of their implementation rather than by name, and code is stored as its AST in a database. This provides a number of benefits:

Unison can be used like any other general-purpose language, or you can use it in conjunction with Unison Cloud for building distributed systems.

Here is some sample code:

-- A comment!
-- Function signatures appear before the definition
factorial : Nat -> Nat
factorial n = product (range 1 (n + 1))

-- Signatures can be left off; they will be inferred
List.map f as =
  go acc rem = match rem with
    [] -> acc
    a +: as -> go (acc :+ f a) as
  go [] as

> List.map (x -> x * 10) (range 0 10)
= [0, 10, 20, 30, 40, 50, 60, 70, 80, 90]

> List.map factorial [1,2,3,4]
= [1, 2, 6, 24]

Functions arguments are separated by spaces instead of parens and commas. Loops are written using recursion (above the helper function go defines a loop). The language supports pattern matching via match <expr> with <cases>, which works for lists and also user-defined data types.

Other resources:

Building using Stack

If these instructions don't work for you or are incomplete, please file an issue.

The build uses Stack. If you don't already have it installed, follow the install instructions for your platform. (Hint: brew update && brew install stack)

$ git clone https://github.com/unisonweb/unison.git
$ cd unison
$ stack --version # we'll want to know this version if you run into trouble
$ stack build --fast --test && stack exec unison

To run the Unison Local UI while building from source, you can use the /dev-ui-install.sh script. It will download the latest release of unison-local-ui and put it in the expected location for the unison executable created by stack build. When you start unison, you'll see a url where Unison Local UI is running.

See development.markdown for a list of build commands you'll likely use during development.

Language Server Protocol (LSP)

View Language Server setup instructions here.

AI Agent Server (MCP)

View AI Agent Server setup instructions here.

Codebase Server

When ucm starts it starts a Codebase web server that is used by the Unison Local UI. It selects a random port and a unique token that must be used when starting the UI to correctly connect to the server.

The port, host and token can all be configured by providing environment variables when starting ucm: UCM_PORT, UCM_HOST, and UCM_TOKEN.

Configuration

See the documentation for configuration here

unison (unisonweb/unison)

haskell
Searching Database…

6.8K ·GitHub
Unison
What is this?Unison is a statically-typed functional programming language with type inference, an effect system, and advanced tooling, built around the idea of content-addressed code where functions are identified by a hash of their implementation rather than a name.
Is Unison a full programming language, or something I add to an existing project?It's a complete, general-purpose programming language with its own compiler, runtime (ucm) and codebase format, not a library. Code is stored as an AST in a database and referenced by content hash instead of by name or file path.
Do I need Stack installed before I can build it?Yes, Stack is the build tool Unison relies on; on macOS you can install it with Homebrew.
Do I have to sit through long compile times like in other languages?No — Unison has perfect incremental compilation with a shared compilation cache baked into the codebase format, so you're almost never waiting for code to compile, and renaming definitions is instant and non-breaking.
What is Unison Cloud used for?It lets you take Unison code you write like any normal program and run it as a distributed system, without switching languages or tools.
Why does content-addressed code avoid merge conflicts?Because definitions are identified by the hash of their implementation rather than text or formatting, Unison's version control is semantically aware and ignores things like import order or whitespace differences that normally cause spurious conflicts.
How does the Codebase web server work?When ucm starts, it launches a web server on a random port with a unique token, which the Unison Local UI uses to connect; the port, host, and token can be overridden with UCMPORT, UCMHOST, and UCMTOKEN environment variables.
What happens to tests when I change code?Unison perfectly caches test results and only reruns deterministic tests when their dependencies actually change, saving redundant test runs.
What are similar projects?morloc, rust-analyzer, epiq, elixir, otp, Benzi, nvim-lspconfig, Nim
Which topics is it in?haskell, language-server-protocol, lsp, functional-programming, version-control, programming-language, compiler, model-context-protocol, distributed-systems, cloud, hacktoberfest, database
Creator
unisonweb
Size
146.1 MB
Stars
6.8K
Updated
CommitOct 15Releaserelease/1.5.0Oct 02
Age
11y
Commits · 90 Days