- Easy to get started: one click install, great website and concise docs. No matter what some people say, getting started in Clojure is a nightmare.
- Lightweight and fresh. No JVM, no Node.
- Freedom and expressivity. Mutable or immutable data structures, ultimately is up to me. It might bite me down the road but for now it feels great.
So we need players. I would rant here, but I won't. But look at this guitar player with blisters. A harpist has blisters, a base player with blisters. There's this barrier to overcome for every musician. Imagine if you downloaded something from GitHub and it gave you blisters. - Rich Hickey (Design, Composition and Performance)
Clojure seems more concerned with power, expressiveness, and reach, rather than ease of use. Does this alienate new users, sure, but the Clojure community seems OK with that as a trade-off.
It's like you were getting blisters from stringing your guitar. You buy a guitar, get home, and it takes three days to open the case. Then another week to figure out which strings go where. God help you when you realize you have to tune the thing.
Two, five, seven days pass and you haven't played a note. I don't think that's what Hickey meant.
That said, it's worth it.
An example would be Clojure's newish approach to managing projects via the CLI and deps.edn. It's very powerful, and expressive, but definitely not a one-click approach.
But as I recall the original Rich Hickey talks on "Why Clojure?" he was explicit that dependency/project management were very hard problems that Clojure didn't really attempt to solve.
I'm not aware of any Clojure tools that are best-of-breed for project management. Java has a better model for locking everything down (or maybe how the Linux Distros manage their repositories) and Python has a better model for just keeping up with the current state of things. I'm not aware of any half-and-half model that gives satisfying results.
Clojure is inferior to Java in that aspect because the number of things to keep track of roughly doubles (for every concept there seems to be a Clojure version and a Java version) and library management is bizarre and warty - see also the horrible import/require/use/some other one I can't even remember mess. And then there is unpicking the syntax differences between using things in the (ns) macro vs calling direct. I dunno; maybe something changed but that part of the experience is a mess. Unusually poorly done in Clojure too, everything else was so lovely.
I never got on top of it and I tried for months; as evidenced I can't even remember how to load a library after putting it down for a little while. Even assuming the classpath is correctly set. What would have to happen for a C programmer to forget #include "name.h" ?
Uh? Clojure locks everything down as a well. In fact, deps.edn solves many issues experienced with Maven.
Personally, I've found Clojure dependency management to be the best I've ever used in any language. It's simple, explicit, gets out of your way, and lets you just do your work.
> and Python has a better model for just keeping up with the current state of things.
I'd like to hear about this? Pip doesn't even have a command to update all dependencies in one go. And figuring what even are the dependencies of any given project is a mess.
For what it's worth, having used Clojure for work for a couple years now, and ditching leiningen for deps.edn (built in package and dependency management that hooks into maven), I've not had an issue with it. You just add the dependencies to your deps.edn, and run your program. If your namespace needs something from a package, you add it to the (:require ...) section of your ns declaration.
Here's an example ns from one of our messiest modules:
(ns profusion.core
(:require
[clojure.core.match :refer [match]]
[clojure.set :as set]
[clojure.string :as string]
[clojure.walk :as walk]
[clojure.zip :as z]
[instaparse.core :as insta]
[profusion.infix :refer [infix-to-prefix]]
[profusion.standard-library :refer [comparison]]
[profusion.utils :refer :all]
)
(:import
(org.jgrapht Graph)
(org.jgrapht.traverse TopologicalOrderIterator)
(org.jgrapht.graph
DefaultEdge
SimpleDirectedGraph)
))
To be clear, projects like this can be run with the base Clojure distribution, no additional tools required.> I'm not aware of any Clojure tools that are best-of-breed for project management. Java has a better model for locking everything down (or maybe how the Linux Distros manage their repositories) and Python has a better model for just keeping up with the current state of things. I'm not aware of any half-and-half model that gives satisfying results.
deps.edn generally asks you for specific versions if you're getting things from maven, so you don't risk not "locking everything down". If you really want to lock everything down however, you should check all your dependencies into your source tree, this is an option that deps.edn supports well, through the :local keyword instead of :mvn/version for maven dependencies. That namespace declaration I showed you is from a subproject that we import into one of our other subprojects using the :local keyword, and the deps.edn for it just declares the source directories and and the dependencies, everything else is handled automatically.
(1) Your way (but also throw in an :only and doesn't mention :refer)
(2) (require 'clojure.contrib.def 'clojure.contrib.except 'clojure.contrib.sql)
(3) (require '(clojure.contrib def except sql))
And leaves open a lot of room for someone to try to use (use) which is probably a mistake since you don't use it.
And sometimes your way has [] and sometimes it doesn't. Pretty much at random considering '[profusion.utils :refer :all]'. And the official docs add in a dizzying number of combinations of quoting requirements to recall.
It isn't the end of the world but that is a far cry from how good all the other parts of the language are. It is really sloppy and confusing to learn. There is no recommended approach and I personally can't remember which easy way I used last time so my personal projects cycle randomly. I think Clojure has the worst library loading mechanism of any language I think is good. Even your way has two completely different code paths (import vs require) to bring in dependencies.
import and require have different purposes though, it makes perfect sense to me that they are separate. Import, here, is used to import Java classes, which don't hook into Clojure's namespaces directly; require is for bringing in symbols from Clojure namespaces. In general, a beginner or intermediate Clojure user will not touch the :import feature at all, nor the :use feature.
> It is really sloppy and confusing to learn.
That's one opinion of it I guess; though in my experience, the way that I do it is very common in publicly-visible Clojure modules. I've been doing it the same way since day one, without issue. There may be other ways, but you don't really need to care about them.
With this you'll understand most modules you come across, and you'll be able to accomplish basically anything you'll want to.
Given the average completeness of documentation on publicly-visible packages (though to be fair most big ones have what most would consider adequate documentation) including the core, you're going to have lots of opportunities to read other people's modules, and these minutiae will fade into obscurity and be overshadowed by your own program's problem space.
> ...it makes perfect sense to me that they are separate...
> A lib’s container is a Java resource whose classpath-relative path is derived from the lib name [0]
> No matter what some people say, getting started in Clojure is a nightmare. ~ galfarragem (earlier in the thread).
I'm hoping this smorgasbord of quotes is making my point for me - the fact that there is an easy way is good, but the problem is that the easy way is very well hidden and Clojure is competing with systems like 'pip install foo', 'import foo' in every single piece of documentation on Python there is on the internet.
I'm not budging from Clojure's import system being byzantine. I don't care that the people who stuck with Clojure figured out something that works for them, it is stupid and it is a very effective filter on keeping people out of the language. The lesson 'ignore half the reference manual page' is not an appropriate lesson to be learning while working out how to load dependencies.
EDIT If all the other parts of the project build were easy then obviously this wouldn't be an effective filter; but this combined with a misconfigured classpath issue for someone who doesn't know Java well would be the end of it.
Getting started in Clojure is not a nightmare, ordinary people do it all the time, the fact that somebody said it was a nightmare says very little.
Clojure's mechanism for requiring packages is far from byzantine, whether you "budge" on that or not; many Clojure libraries have the snippet for including the current stable release of that library at the top of their README on GitHub. It isn't matter of "sticking with it" or "figuring out something that works for you", it is literally one relatively simple piece of knowledge that is learned once and works forever.
In short, if you find namespaces and importing byzantine in Clojure, you are probably at the level of struggling to write fizzbuzz in any language. The fact that there are features other than :require in ns does not indicate that :require is complicated, it just indicates that ns has features.
Somehow a language designed from scratch with all the purported wisdom of Lisp ended up with a nastier import solution than JavaScript, which had none out of the box for its first two decades of life, and then had to reconcile as many as 5 different module systems.
Also Clojure is doing just fine, not sure what you mean by "dying". The core and the tooling continue to improve, there are lots of libraries, more people writing than ever. I just don't see this death you're describing.
The comments here just strike me as ignorant and incoherent as a whole. Why do people who clearly have no experience actually trying to do something in Clojure have so much to say about it?
Clojure may support things that look daunting to you, but if you actually had any goal other than critiquing the variety of things you actually have no use for, you would not have the difficulties you describe.
Maybe I'm spoiled, I remember JDK setup being a pain on Windows a decade ago when I used it last, if that's the problem then I get it. My spoiled experience on a system with a functioning package manager is basically install-and-go, and zero configuration required to get CIDER going after that.
I just don't get what's so bad about it, it's basically the same experience as Rust with Cargo; is that another "nasty" experience? What language with package manager has a better experience?
>...
>To be clear, projects like this can be run with the base Clojure distribution, no additional tools required.
Didn't you just say that dependency management hooks into Maven? So doesn't that imply you need to get Maven set up before you can run a Clojure project?
Not sure what is meant by "get Maven set up". With Clojure it does not involve any additional work, it's just built in to the Clojure runtime, and it goes ahead and fetches your dependencies either when you ask it to, or right before loading your program for the first time.
I think they just use the Maven repositories, as in the servers themselves, not the Maven client software for Java, whatever that may be (I've never used it).
You just need Java installed on your system, then you install clojure (via brew, or sh install) and that's it, you're good to go.
I've written a guide to starting with Clojure covering installation to REPL & IDE configuration: https://grison.me/2020/04/04/starting-with-clojure/
In an extreme case, someone who doesn't know Java ecosystem might want to stop to research: what is JVM, why is it necessary, which version would be the best, what's the difference between Oracle's Java and OpenJDK, etc...
Out of the top of my head:
- There is the Python 2.7/3.X situation still going on, then there are the several distributions of python.
- GNU's R has a similar problem
- Installing gcc on windows was (perhaps still is) a confusing mess for a newcomer.
IMO I did not find installing clojure any harder than installing Scala for instance, and yet I have never heard (anecdotal, I know) complaining about Scala.
You might not share that users preference of caring about the installation experience of a PL, but arguing that this user's preference is somehow unfair because many other languages also have bad installation experiences makes absolutely no sense.
The vast majority of PCs are Windows, not Mac or Linux. Though WSL2 (available with Windows Insiders) makes working with Linux software a breeze, it's not the standard flow. Java isn't installed by default, either.
Your guide suggests using WSL and IntelliJ. Does IntilliJ actually work with Closure running in WSL? For that matter, does the VS Code plugin?
These are all headaches a new programmer won't have when getting setup with PHP, Python, JavaScript or most popular languages.
I think this is especially disappointing because there are mature, cross platform solutions available but whoever manages the Clojure project seems hell bent on pushing their "clj" tool which is, clearly, treating cross-platform concerns as an after thought. The Clojure organization conducts a survey every year and this is hurting their adoption with developers on Windows.
"One new question we asked this year was about the primary developer operating system to give us better guidance about tool-related work. As expected, MacOS was the leader (55%), followed by Linux (35%) and Windows (9%)"
Getting started with Leiningen, in my opinion, is much easier although, as has been pointed out, installing a JDK is an extra step that other languages don't have.
[0]: https://clojure.org/guides/getting_started
[1]: https://clojure.org/news/2020/02/20/state-of-clojure-2020
I'm doing a lot of Clojure since years both on my MBP and on Windows and there's no problem at all doing that way. Besides VSCode even has a plugin for WSL which will let you directly hook into it.
So yeah there are some questions like which Java to install, which IDE, .. but these questions are the same for other programming languages.
If you have any hint regarding how to improve my guide don't hesitate to tell me if something is not clear in it :)
Probably the biggest thing would be to assume the person reading the guide has a brand new computer and hasn't installed anything yet (including Java and Homebrew).
It's really hard to assume much about the background of someone just trying a new programming language. Maybe they've worked with other languages and you're familiar with, maybe not.
A Lisper sees a REPL, and thinks they have "gotten started." When I think most language learners don't think they have "gotten started" until they, on the low end, have printed something at a familiar terminal, or, on the high end, pointed a web browser to localhost:8080 and seen some text there.
I don't see who the "clj" shell script is somehow "part of Clojure" any more than Leiningen or Boot. IMHO it's just a shell script and it works similarly to the other tools, except not in any way cross platform.
"Then run:
Invoke-Expression (New-Object System.Net.WebClient) .DownloadString('https://download.clojure.org/install/win-install-1.10.1.536....
There's also no clj installer for Windows although there is a Scoop package.
https://github.com/clojure/tools.deps.alpha/wiki/clj-on-Wind...
And how to work with vscode as it all fails, at least windows.
But love clojure syntax. In particular I found it hard to see all () and the simple added some syntax sugars help the eye a lot.
Hence jump to janet. In fact the community is very helpful.
Not sure but the size is small enough to see whether one can do embedded as I try picolisp but it is bounded to a low end Env.
Very promising.
Btw the whole point I later schedule more time to try clojurescript to ... May be that can wait a bit.
2 - Dowload clojure.jar
3 - Start command.com or PowerShell
4 - cd into clojure installation directory
5 - java -jar clojure.jar
What there should be is an exe or MSI installer like every other Windows program.
Not directly the link you provided.
Yes, they require Java knowledge I guess, but then again using guest languages without caring for the host platform is a fallacy.
Now I do agree that an installer would be the right experience to provide.
1. Alpha version of "clj on Windows", which seems to be the recommended approach, and requires going to another page to get the instructions.
2. Homebrew on Linux or Windows with WSL, linked to under "Installation on Linux".
3. Build from source, under "Other ways to run Clojure", which assumes git, Java, and Maven installed, with no instructions on how to install them.
I would say it's pretty confusing from that what is the optimal, recommended way to install Clojure on Windows. It might be better to have subheadings under "Installation on Windows" like "For Java developers" (assuming Java tools already installed), "For WSL users" (Homebrew), "For Powershell users" (clj on Windows). This would consolidate the Windows installation strategies and reflect the diversity in the Windows developer population. Some are already full time Java developers, some live in WSL as much as possible, and some fully embrace Windows specific tools like Powershell.
...
2 - Download clojure-1.10.1.jar, spec.alpha-0.2.176.jar, core.specs.alpha-0.2.44.jar from mvnrepository.com
...
5 - java -cp clojure-1.10.1.jar;spec.alpha-0.2.176.jar;core.specs.alpha-0.2.44.jar clojure.main
2 - Dowload clojure.jar
as a shorthand for
2.1 - Install Maven
2.2 - Install git
2.3 - Clone https://github.com/clojure/clojure.git
2.4 - Run mvn -Plocal -Dmaven.test.skip=true package
It used to be so that they provided a zip to download.
In any case as mentioned on a sibling comment, I assume that anyone willing to use a guest language should get comfortable with the host platform.
So git, well for better or worse that is what most are using nowadays.
Maven, number one build tool on Java world, even if using another one, most likely those jars are coming from Maven Central.
Just like, regardless of my opinion on C, I keep my C knowledge up to date, because that is what I eventually might need to reach to when on UNIX like platforms.
command.com? Is it 1995?
CL is a breeze. Even installing new dependencies into a running image is a breeze, and no need to restart anything.
You don't even need to leave the REPL!
Idunno, I read the whole homepage and I don't really know where to go to download it. Is "clone and run Meson" what you meant by "one click install"?
> No matter what some people say, getting started in Clojure is a nightmare.
On my distro I just do pacman -S clojure and I have a working clojure environment, on everything else it's usually available as one package. Not much of a "nightmare" to my eyes, at least when compared to Janet, which doesn't tell you how to install it anywhere on the website.
As far as language features, I miss a lot from clojure: immutable/persistent data structures, protocols, not to mention concurrency primitives. But Janet's approach to performance and design is "do less". With the C api you can easily add bindings to some C library that provides a desired feature. But even without that stuff, Janet is for me a python-killer, if not a clojure killer.
Edit: at any rate, I think it's not meant to be a competitor to Clojure, its similar syntax just often invites the comparison. It's much more fair to compare it to Lua.
There is Guile https://www.gnu.org/software/guile/ that is an implementation of Schema with the focus on being an extension language that integrates with C and C++. Wouldn't it more practical to adopt and contribute to it, rather than invent an own wheel?
Firstly, this is a rather silly argument in general. One could say that Embeddable Common Lisp and Guile address the same niche and all developers from one project should consolidate in the other.
I have not used Guile to any extent, nor was Janet really influenced by it, but the comparison has been brought to my attention several times in the past. Janet is not scheme nor common lisp, so there are of course many differences that I cannot address here. However, as an extension languages, there are several things that I believe Janet does better than Guile.
Guile is not an ideal extension language for C projects (this is distinct from an extension language for GNU projects). Firstly, they address garbage collection with the Boehm GC, which takes some control over your runtime and is not known for great performance (the runtime/non standard C is the bigger issue). This was of course a decision made by Guile devs to make it easier to write correct bindings to C libraries in Guile, but it is not without it's downsides. Secondly, the project is not easy to embed in foreign build systems. Janet is more like Lua - built in tracing GC that is not conservative nor platform specific, no external dependencies beyond libc, and can be added to a project as an amalgamation (a single C file and 2 header files). This has enabled people to get Janet running more easily on a variety of platforms like mobile phones and even recently someone has been doing some work on getting Janet running on the Nintendo Switch. I believe Janet is also significantly smaller than even the smallest build of guile. Basically, Guile is not simple, which is (IMO) antithetical to an ideal extension language.
At the same time, Janet should feel like a much less minimal language compared to Lua. While core Lua limits itself to pretty much only standard C, Janet goes a little further to provide some abstractions over different platforms (that can be turned off via compile time options).
My argument can sound silly, particularly considering the fact that you do not have any obligations to justify your project that you opened for others. I am very thankful to open source contributors, but I have a feeling that many open source languages, frameworks, libraries, and desktop environments would be more popular, polished, and maintained, if we could compromise, tolerate, and control our ego or creativity, and contribute to existing projects.
I think, we can see the benefits of focus and discipline by comparing Rails and its gem ecosystem with “blossoming thousand flowers” of Node.js web frameworks.
This goes back to another discussion here: just because you've implemented a language doesn't mean you've implemented it well. Sure, I can implement all the syntax of what I want. But is it fast? Does it report errors well? Am I enforcing my type system, or can I accidentally drop back into normal Scheme?
I think a lot of times new Lispers learn macros and, drunk with their newfound power, start writing 20% implementations that get them 80% to mature languages. And if you don't need or want the other 20% of a mature language, then that's fine. But if you do need or want the other 20% of a mature language, then you'll quickly discover that the Pareto Principle[1] applies. Lisp metaprogramming can be super powerful, but it's not a magic bullet: not only does it not kill werewolves but you can shoot yourself in the foot with it.
[1] https://en.wikipedia.org/wiki/Pareto_principle#In_computing
OO is overrated but most apps have some state and I found the entity-component systems solid but not still unwieldy.
Clojure has really great concurrency primitives; all the semantics I could want built right in. Except my concurrency often occurs in the persistence layer, and unless I'm also writing that layer, Clojure can't help me. Persistent/immutable data structures are amazing.
The delimiters IMO are a vast improvement over most other lisps (especially for creating specific data types).
Clojure's startup time is pretty brutal for a lot of things I'd like to use it for, and no amount of REPL-driven development can make Clojure appropriate for CLI tools.
If you got the repl-driven development down, you wouldn't test your CLI by launching it, you would just evaluate the same functions as the CLI uses. Only time when you'd want to launch the CLI would be before releasing a build or for E2E tests. Once you got the code down for your repl and the startup time becomes a hassle, you compile down your Clojure program to a binary with GraalVM and now it starts up fast.
Otherwise, give babashka a try. Basically single-binary Clojure environment. https://github.com/borkdude/babashka
GraalVM simply is not production-ready, though I follow its progress with great interest. That said, it's hard to compare the process of integrating with GraalVM against a language that actually just has fast startup.
Babashka is pretty cool, but it's another example of something that isn't quite Clojure. Nice if you can tolerate various "almost the same" languages, but Clojure itself is still weak in these domains.
And while Babashka is not Clojure, it's interpreter (sci - https://github.com/borkdude/sci) is in fact a "Small Clojure Interpreter" that tries to stay as close to Clojure as possible. Unless you're using the Java interop, I've yet to hit anything I cannot do in Babashka that I could do in Clojure (I barely use Java interop)
Managing distributions for a bunch of different architectures is difficult.
- VMs, not OSes, are the platforms of the future, so target the JVM
- Object Orientation is overrated, but polymorphism is a good thing
- Multi-core is here to stay, so use immutable data structures to greatly facilitate writing correct concurrent programs
- Leverage the strengths of LISP but give it a modern overhaul (most notably, throw in different parenthesis)
...but then again, who reads on a mobile device anyway (j/k) ;-)
I'm always flabbergasted about the ignorance against the JVM on this site. There is nothing out there that has seen similiar research and optimisations and has so good monitoring/debugging tools.
It shouldn't have happened in a production environment, but setting up a way to lose tens of thousands of dollars if performance is bad, trusting unreasonable numbers, trying to produce no garbage, and requiring no GC pauses because margins are too tight are all your faults, not a shortcoming of your JVM.
It's my fault that if you trade US equities based on old information you lose money?
Edit: Actually, I'm still not sure how to correctly measure GC pauses, other than from inside the application.
Can you explain how Java was chosen for your trading application? Also, why were you unable to test it properly?
The application was tested in an environment that's a lot like production, except that we had substantially fewer cores than an exchange running the same number of matching engines, so the incoming ticks were a bit less bursty. That burstiness was important in this instance. A big reason for the differences between the production environment and the test environment was the cost of hardware.
No criticism, as I've only read others' accounts, but that sounds out of character.
What's "out of character" (nice euphemism!) is adopting state of the art automatic garbage collection technology, writing in a language that makes actual garbage collection practically unavoidable, and then expecting that garbage collection doesn't happen or happens accordingly to arbitrary expectations. The JVM is clearly inappropriate technology if latency is important: it can perform well in common cases and with a reasonable level of tuning effort, but other options simply do not have the threat of GC pauses.
I'm sorry to say it, but the loss of money here was not the JVMs fault. It was putting code with insufficient load testing in a production environment and crossing your fingers despite the fact that serious money was on the line.
Considering that software mishaps in securities trading can annihilate a company of any size, not only cost you as much as a bunch of servers, lack of testing appears very reckless.
We did not generally physically swap out servers each time we changed a line of code. Rather, we had two identical sets of servers, one for production and one for test. For test, we had some additional machines to run matching engines. If we wanted to make the test environment more closely match an actual venue, we would need many more machines that run matching engines. That still might not be sufficient to produce identical output timings in prod and test, though, because venues generally do not publish the sequence of all incoming ticks they receive during a day, the source code of their matching engine, what hardware they are using, their kernel version, and so on.
> Considering that software mishaps in securities trading can annihilate a company of any size, not only cost you as much as a bunch of servers, lack of testing appears very reckless.
It's strange that you replied to me suggesting we had no production-like test environment ~10 hours after I replied to you saying that this code did fine in our production-like test environment.
Can you jump over 64Kb in bytecode yet? Allocate a lexically scoped variable?
Of course, enormous amount of work has been put into making this particular pig fly at reasonable speed. Doesn't change the fact that most usability complaints about Clojure stem from reliance on JVM piggybacking.
Tuning can be a pain, but scaling anything is hard.
Kotlin, from the little I've seen, appears to be largely a syntactic variation of Java, so there is certainly good impedance to JVM. Clojure is less so, and here lies the reason everyone curses about its backtraces.
Clojure is in a bad spot here, it was a good idea at the time but not today. Clojure relies on Java for its libraries cause Clojure has almost no ecosystem. 95% of Clojure libs are Java wrappers.
Without Valhahla we will never get a Java variant of Unity, jMonkey Engine is a good as it gets and it has plenty of native code to overcome the areas where the JVM is found lacking.
[1]: A different philosophy that gives more control to the user in exchange for explicitness puts it ahead in some areas (structs) and behind in others (compilation quality, GC), but as a runtime engineer it's "technologically" behind (I work on OpenJDK so I'm biased, but I came to work on OpenJDK because that's where most interesting innovation in runtimes happens).
People who wrote WCF services in VB for a living are probably extremely disappointed.
Whilst WCF made some notable improvements over what existed within the ecosystem before it, it was still a sprawling, complex PITA and full of developer friction. Killing it off in this case was definitely the right thing to do :-)
I think their biggest weakness now is branding (.NET vs .NET Core). This will be fixed with .NET 5, which merges the two and will make all flavors of .NET cross-platform.
right now if you release binary software for linux, windows and mac, you basically have 3 versions to distribute.
that will turn into 9 versions per release. that's a build and release nightmare.
Other than that, good points.
You can do LINQ style coding in Smalltalk-80, and modern Smalltalks like Pharo do support traits as well.
So the point being that all major languages embrace both paradigms.
"Traditional OOP" basically boils down to Java until version 8 or C# until version 3, and very little else, but unfortunately most teachers fail at giving overviews of programming languages thorough computing history, and many just learn what they can reach out for.
> So the point being that all major languages embrace both paradigms.
Sure, nowadays, most languages are very much multi-paradigm, but typically there is a dominant paradigm and the others are somewhat second-class. For example, in recent years, Java has gained a lot of functional programming feature too, but its not in the same ballpark as Haskell.