Function reuse/sharing is minimal (We don't have a redo yet, though). Launch VS Code Quick Open (Ctrl+P), paste the following command, and press enter. If you're interested in the Unison programming language (unisonweb.org) and attending Strange Loop this year, join this group! You'll only rerun a test if one of the individual definitions it depends on has changed. JavaScript falls in the first category. Introduction to the Unison programming language Unison is a new purely functional programming language, currently under development. Now that we've added our square function to the codebase, how do we reference it elsewhere? At the Strange Loop conference in St. Louis, Missouri, earlier this month, Paul Chiusano, founder of Unison Computing, gave the audience a tour of Unison, an emerging programming language designed for building distributed systems. The dependency tracking for determining whether a test needs rerunning is 100% accurate and is tracked at the level of individual definitions. Have a look at `nix-copy-closure` for example. Let's try this out. My book, Functional Programming in Scala, uses Scala as a vehicle for teaching FP. The > square 4 on line 6 of the file, starting with a > is called a "watch expression", and Unison uses these watch expressions instead of having a separate read-eval-print-loop (REPL). Unison is a functional language that treats a codebase as an content addressable database[1] where every ‘content’ is an definition. It's a modern, statically-typed purely functional language, similar to Haskell, but with the ability to describe entire distributed systems with a single program. graphic-homepage-hero. That is, it adds a line starting with --- and puts whatever was already in the file below this line. Because of the append-only nature of the codebase format, we can cache all sorts of interesting information about definitions in the codebase and never have to worry about cache invalidation. The prompt shows us which namespace we are currently in. In Unison, the ‘codebase’ is a somewhat abstract concept (unlike other languages where a codebase is a set of files) where you can inject definitions, somewhat similar to … If you haven't already, you should totally check out Brian Tiffin's awesome Unicon Programming Page. Now put the following in your scratch file: This defines a function called square. Unison: a friendly programming language from the future unison.cloud: the worldwide elastic computer (coming soon) Type systems and UX: an example CSS … Try doing edit square from your prompt (note you can use tab completion): This copies the pretty-printed definition of square into you scratch file "above the fold". Notice that Unison inserts precise use statements when rendering your code. For example, x -> x + 1 (a definition) as opposed to Nat.increment (a name we associate with it for the purposes of writing and reading other code that references it). Consider this: if definitions are identified by their content, there's no such thing as changing a definition, only introducing new definitions. This is the basis for some serious improvements to the programmer experience: it eliminates builds and most dependency conflicts, allows for easy dynamic deployment of code, typed durable storage, and lots more. I'm looking for some features that are useful to the everyday programmer and that would be interesting to implement. Unison Computing is hiring an Infrastructure Engineer, see our jobs page! ... We will introduce bits and pieces of the core Unison language and its syntax as we go. Code is published using the push command and libraries are installed just via the pull command (recall how in the quickstart guide, we installed the base libraries with a pull). Read what people are saying about it.. Popular links. About Unison:Unison is a new programming language, currently under active development. There's one more ingredient that makes this work effectively, and that's functional programming. When editing scratch files, any relative names not locally bound in your file will be resolved by prefixing them with the current namespace of .mylibrary. I'm currently writing a bytecode interpreter for a compiled programming language I am going to make in the near future. Unison is a typed language largely influenced by Haskell, Erlang and a research language called Frank. He has over a decade of experience with purely functional programming in Haskell and Scala and coauthored the book Functional Programming in Scala. To make this happen, Unison just changed the name associated with the hash of foldl in one place. Installation. Unison treats any … The square function and the tests we've written for it are not yet part of the codebase. Haskell, Elm, and Clojure are probably your best bets out of the 27 options considered. 52.7k members in the ProgrammingLanguages community. It's all good! Let's rename that to List.foldLeft to make things clearer. Copy. What may change is how definitions are mapped to human-friendly names. We'll do that shortly, but first, let's try calling our function right in the scratch.u file, just by starting a line with >: That 6 | is the line number from the file. Each Unison definition is some syntax tree, and by hashing this tree in a way that incorporates the hashes of all that definition's dependencies, we obtain the Unison hash which uniquely identifies that definition. In the meantime, anyone is welcome to help with alpha testing. Names in Unison look like this: math.sqrt, .base.Int, base.Nat, base.Nat. As I said, I rename things obsessively, but this has a cost. To keep our root namespace a bit tidier, let's go ahead and move our definitions into the mylibrary namespace: We're using .square to refer to the square definition directly under the root, and then moving it to the relative name square. Wholly based on a talk by Paul Chiusano. Absolute names (like .base.Int) start with a . Let's try this out. This page is powered by a knowledgeable community that helps you make an informed decision. Notice that Unison has put the correct type signature on square. Unicon has switched to Git. Though a lot of the work on Unison is still experimental and ongoing, we’re sharing an early alpha release of the language for you to test out. So how does that work? We often think of these names as forming a tree, much like a directory of files, and names are like file paths in this tree. That would be crazy, right? Twitter • GitHub • LinkedIn • RSS. There's some new syntax here, explained afterwards: This will test our function with a bunch of different inputs. Unison Runtime. This document covers the details of how to organize your codebase, issue and review pull requests, install libraries, and make releases. When any such file is saved (which we call a "scratch file"), Unison parses and typechecks that file. What if they're expensive? Unison’s core idea is that code is immutable and identified by its content. Let's add a test for our square function: Save the file, and Unison comes back with: The check function has type Boolean -> Test.Result. As a result, a Unison codebase can be versioned and synchronized with Git or any similar tool and will never generate a conflict in those tools. For instance, if we added x = 42 to our scratch file and then did .mylibrary> add, that would create the definition .mylibrary.x. If we were in a different namespace, we would need to change the pull command from using the relative path base to the absolute path .base. Functional programming, UX, tech. This document introduces "the big idea" behind Unison and walks through the basics of using the Unison codebase manager to develop and publish your first Unison library. The first line, use .base, tells Unison that you want to use short names for the base libraries in this file (which allows you to say Nat instead of having to say base.Nat). Unison takes the concept of Nix further and instead of just giving each package a unique identifier, it gives one to every semantic unit in a codebase. Unison is an open source functional programming language based on a simple idea with big implications: code is content-addressed and immutable. or install it on your computer If we do test again, we'll get the newly cached results. Here's a link to Unison's open source repository on GitHub. When taken to its logical endpoint, this idea of content-addressed code has some striking implications. Use undo to back up a step. There's no separate tooling needed for managing dependencies or publishing code and you'll never encounter dependency conflicts in Unison. Feedback and improvements are most welcome! Unison's type system won't let you do I/O inside one of these watch expressions or anything else that would make the result change from one evaluation to the next. But let's be honest that it's a compromise, and not forget to improve things later. Paul Chiusano started the research that led to the Unison language and is a cofounder of Unison Computing, a public benefit corp. Let's add it now. Also see the guide on organizing your codebase and day-to-day workflows. The view command just looks up the names for the hashes on the fly, right when it's printing out the code. This is the Unison Codebase Manager starting up and initializing a fresh codebase. While you can use functional programming paradigms in the language, you can just as easily use an object-oriented approach. That is why I was surprised by the refactoring capacity of this new programming language called Unison. Eff is a functional programming language based on algebraic effect handlers.This means that Eff provides handlers of not only exceptions, but of any computational effect, allowing you to redirect output, wrap state modifications in transactions, schedule asynchronous threads, and much much more…. Deployment can be done in a similar way to Nix too. All the tests had been run previously and cached according to their Unison hash. Read. Keep your ucm terminal running and open up a file, scratch.u (or foo.u, or whatever you like) in your preferred text editor (if you want syntax highlighting for Unison files, follow this link for instructions on setting up your editor). Be introduced to the new programming language Unison! If a result for a hash is in the cache, Unison returns that instead of evaluating the expression again. For example, when renaming a function, you have to modify all references, or, what is the same, you have to modify all the files where there are functions or methods that invoke the renamed function. Unison syntax highlighting for VS Code. Copied to clipboard. In Unison we call this something else the Unison Codebase Manager. *, ++, or foo. square should have the property that square a * square b == square (a * b) for all choices of a and b. Let's test this a bit more thoroughly. It's an open source statically typed functional programming language and it's currently in public alpha testing. The Unison namespace is the mapping from names to definitions. Let's introduce some Unison syntax: Try doing view base.List.foldl if you're curious to see how it's defined. Haskell, Erlang, and Frank walk into a bar – and begin new project to work in Unison . We’ll make a more finished release generally available soon. It began as an experiment: rethink all aspects of the programming experience, including the core language, runtime, tooling, as well as code versioning and publishing, and then do whatever is necessary to eliminate needless complexity and make building software once … Unisonweb.org is a low-traffic web project, safe and generally suitable for all ages. It takes a Boolean expression and gives back a list of test results, of type [base.Test.Result] (try view Test.Result). Unison will have a uniform feel in accordance with the community's overall opinions. > Unison is a new programming language, [...] similar to Haskell, but with a unique ability to describe entire distributed systems with a single program. Syntax highlighting for the Unison programming language. Both Unison and rsync use the so-called “rsync algorithm”, a type of delta encoding, for performing updates. ☝️ Using alias.term instead of move.term introduces a new name for a definition without removing the old name(s). We're used to thinking about our codebase as a bag of text files that's mutated as we make changes to our code, but in Unison the codebase is represented as a collection of serialized syntax trees, identified by a hash of their content and stored in a collection of files inside of that .unison/v1 directory. In this case there was only one result, and it was a passed test. December 15, 2019 Tweet Share More Decks by Philip Schwarz. Great! reverse is defined using List.foldl, where l is a needless abbreviation for left. and are paths from the root of this tree and relative names (like math.sqrt) are paths starting from the current namespace, which you can set using the namespace (or equivalently cd) command: Notice the prompt changes to .mylibrary>, indicating your current namespace is now .mylibrary. The testing library supports writing property-based tests like this. Unison: A Content-Addressable Programming Language By 0x000216. unison A friendly programming language from the future programming-language haskell unison unison-language Haskell 174 3,558 473 (63 issues need help) 15 Updated Jan 5, 2021. base Unison base libraries unison unison-language 13 21 4 1 Updated Dec 15, 2020. unisonweb-org In a purely functional language like Unison, tests like these are deterministic and can be cached and never run again. A big question that arose: even if definitions themselves are unchanging, we do sometimes want to change which definitions we are interested in and assign nice names to. Adios, SVN, you served us very well. It typechecked the square function and inferred that it takes a natural number and returns a natural number, so it has the type Nat -> Nat. Nice! Paul Chiusano. Don't worry about picking a perfect name the first time. That is: an optional ., followed by one or more segments separated by a ., with the last segment allowed to be an operator name like * or ++. If you're curious to learn about the guts of the Unison codebase format, you can check out the v1 codebase format specification. At Lambda World Seattle Co-Founder of Unison Computing, Rúnar Bjarnason find out all about the Unison language, its type system, developer experience, all that makes Unison unique. Is it really feasible, though, to build a programming language around this idea? It’s a modern, statically-typed purely functional language, similar to Haskell, but with a unique ability to desc It's not arbitrary or strange, but a logical and sensible choice with tremendous practical benefits. "Forces you to learn pure functional programming" is the primary reason people pick Haskell over the competition. It's similar to Go and is also influenced by Oberon, Rust, Swift. So far they only exists in our scratch file. Here we'll make a change to the implementation of our square function. The Unison namespace is the mapping from names to definitions. Unison is an open source functional programming language with special support for building distributed, elastic systems. Install →. ☝️ The use statement can do absolute names as well, for instance use .base.List map. Luckily, Unison keeps a cache of results for expressions it evaluates, keyed by the hash of the expression, and you can clear this cache at any time without ill effects. We will often do use .base at the top of our file to refer to all the basic functions and types in .base without a fully qualified name. Try it out in your browser! But the longer you spend with the odd idea of content-addressed code, the more it starts to take hold of you. The code you are editing can be run interactively, right in the same spot as you are doing the editing, with a full text editor at your disposal, with the same definitions all in scope, without needing to switch to a separate tool. !nat generates one of these numbers. Unison Computing @pchiusano. When first launching Unison in a new directory, we get a message like: No codebase exists here so I'm initializing one in: .unison/v1. Some programming languages allow functional programming while others either encourage or even enforce it. Is the codebase still just a mutable bag of text files, or do we need something else? The fact that things were done a certain way in the 1970s is not a good reason to keep doing them, especially if they make programming worse. Let's try that: If we rerun the tests, the tests won't be cached this time, since one of their dependencies has actually changed: Notice the message indicates that the tests weren't cached. Overview Version History Q & A Rating & Review. It also tells us that square is "ok to add". Try out the following command (you can use tab completion here if you like): Notice that view shows the foldLeft name now, so the rename has taken effect. That is: an optional ., followed by one or more segments separated by a ., with the last segment allowed to be an operator name like * or ++. So one thing that's useful and easy to maintain is an index that lets us search for definitions in the codebase by their type. The use .base is a wildcard use clause. *, ++, or foo. Unison is a cross-platform music production studio. We do need something else to make it nice to work with content-addressed code. Unison Computing is hiring an Infrastructure Engineer, see our jobs page! When you're starting out writing some code, it can be nice to just put it in a temporary namespace, perhaps called temp or scratch. How do you refactor or upgrade code? We'll be coordinating some a meetup at or near one of the conference venu Unicon 13.1 Binaries are now available for download at sourceforge. This is important: Unison isn't doing a bunch of text mutation on your behalf, updating possibly thousands of files, generating a huge textual diff, and also breaking a bunch of downstream library users who are still expecting that definition to be called by the old name. Unison is different to rsync, which is a mirroring tool. nat comes from test - test.nat. About my book. Part of the fun in building Unison was in working through the implications of what seemed like a great core idea. When rendering code, a minimal set of use statements is inserted automatically by the code printer, so you don't have to be precise with your use statements. Intercommunication is difficult, done mostly via APIs. © 2019 Unison Computing, a public benefit corp and contributors • this site on GitHub. Names in Unison look like this: math.sqrt, .base.Int, base.Nat, base.Nat. Download Unison - Music Production Studio for free. To build unison programming language programming language with special support for building distributed, elastic systems added our square.... Us use anything from the base namespace under the root, so square and its syntax we! Helps you make an informed decision the differences quality ) a brief introduction to the of... Change is how definitions are mapped to human-friendly names is also influenced by Oberon, Rust Swift... Tremendous practical benefits have programming be reasonable want to learn about the guts of the 27 options.! 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