A friendly programming language from the future.
helloWorld : '{IO, Exception} () helloWorld _ = printLine "Hello World"I wouldn’t call it friendly.
Brackets and parens flipped is an instant no thank you. Bad design
Although, i would agree with it not necessarily being “friendly”, since its a drastically different syntax than many beginners would be used to, the brackets and parenthesis here are not what you think they are.
Unison is a language in the style of Haskell, F#, Purescript, Elm, etc. So that first line is actually type annotations.
In Haskell, this would just be
helloWorld :: IO (), meaning a function named “helloWorld” with no arguments and produces what is essentally a potentially-unsafe IO action with a Void return (the empty parenthesis () ).Here in Unison they call the bracket part “abilities” or something. Its saying the same thing as Haskell, but being more explicit in saying it can raise an exception.
Yeah sorry - that’s just unnecessarily obtuse. Programming languages just don’t need to be that convoluted. Hello world should look something like this:
print("Hello, World!")And when you need more complexity, it can still be far simpler than Unison (or Haskel). For example this (in Swift):
func processNumbers(_ numbers: [Int]) -> [Int] { return numbers.filter { $0 % 2 == 0 }.map { $0 * $0 } } let numbers = [1, 2, 3, 4, 5, 6] let processedNumbers = processNumbers(numbers) print(processedNumbers)
Literally the opposite of friendly. Already in the hello world you have two imports for extremely basic functionality (why should I have to import the ability to throw exceptions??) and a completely enigmatic symbol ’ that apparently has a significant function.
A “friendly” programming language should be readable without knowing esoteric symbols.
Really got my hopes up with that headline that it’d be a python-level intuitive-to-read language with static typing.
What you expected sounds more like what nim offers.
python-level intuitive-to-read language with static typing
Agreed, this is exactly Nim
There are no imports, these are type annotations
Do I really have to declare that something requires exceptions?
Yes, in functional programming you want to use pure functions. Exceptions are impure, therefore it has to be declared.
Other functional languages don’t even have exceptions
This looks like the opposite of friendly to me. Is it supposed to be targeted towards cloud computing or web apps? I don’t really understand what its ideal use case is.
Oh, it’s weird ugly Haskell!
… I can write weird, ugly Haskell in Haskell, though.
Looks intriguing, reading a bit … some concepts look like they came from Nix
As a F# lover I really want to see Unison take off
There take on what they call capabitilites is very interesting. Basically anything that would make a function non-pure seems to be declared explicitely.
A computational effect or an “effectful” computation is one which relies on or changes elements that are outside of its immediate environment. Some examples of effectful actions that a function might take are:
- writing to a database
- throwing an exception
- making a network call
- getting a random number
- altering a global variable
“Capabilities” is the new “Functional Programming” of decades prior,
Scala is also expanding in this area via the Caprese project: https://docs.scala-lang.org/scala3/reference/experimental/cc.html and it promises Safe Exceptions, Safe Nullability, Safe Asynchronicity in direct style/without the “what color is your function” dilemma, delineation of pure vs impure functions, … even Rust’s borrow checker (and memory guarantees) becomes a special case of Capabilities.
I believe this is a major paradigm shift, but the ergonomics have yet to be figured out and be battle-tested in the real world. Ultimately, like for Functional Programming Languages (OCaml, F#, Haskell, …) I don’t expect pionniers like Unison/Koka/Scala to ever become mainstream, but the “good parts” to be ported to ever the more complex and clunky “general purpose” programming languages (or, why I love Scala which is multiparadigm and still very thin/clean at its core).
It’s not really fair to state that functional languages aren’t battle tested or imply they aren’t useful in real world problem solving, Erlang/Elixir prove that.
functional languages aren’t battle tested or imply they aren’t useful in real world problem solving
Yup, I never said that, though? What I was about was to draw a parallel between functional programming languages and explorations from several decades ago vs the new languages and explorations going into effect typing/capabilities programming now (and the long way ahead for those).
What I find interesting is that those pioneering FP languages never came to top the popularity chart, implying that I’m not expecting Unison to be different (but the good parts might make it into Java/C#/Python/… many years from now).
I think that when it comes to functional programming with effect systems, unison is currently the closest to showing how it is actually done. Koka and languages like Effekt are of course very nice, but they don’t show much going for them besides the example nondeterminism and exception effect. Verse, that language that was going to be used as Fortnite’s scripting language, also plans on adding these effect systems a la Koka.
Overall, I think one of 2 things will happen:
- unison will slowly gain more and more adoption and grow out to become a formidable niche language
- Verse will blow unison out of the water and everyone who once even considered unison will be moving to Verse instead
This hurts my eyes to look at
The distributed computing aspect is very interesting, but the documentation is a mess. I applaud trying to use different and understandable terms than Haskell and other functional languages (monad, monoids, functors, applicative functor, etc.), but the examples are too verbose.
Concerning distributed computing, writing code that seemingly has no boundaries would be a major step forward for web development. Having to split models between client and server, come up with an API that follows some convention, find a solution for client-library generation, and so much more, is tedious, repetitive, and error-prone. Having most of that handled and having blurred boundaries would make writing web applications pleasurable again.
At the moment, unison looks like an iteration on the right path, but there is a lot of work to do in making it accessible and understandable.
