What are the best Functional languages to learn for web-frontend development?

Question

13

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Considered

238

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Recs.

Oct 1, 2019

Last
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Here’s the Deal

The Best 1 of 12 OptionsWhy?

Best Functional languages to learn for web-frontend development	Price	Site	Price
90 Elm	-	http://elm-lang.org/	Open Source
-- Reason ML	-	-	Free, Open source
82 ClojureScript	Open Source	https://clojurescript.org/	Open Source
-- F#	-	http://www.fsharp.org	-
-- Purescript	-	-	-

See Full List

11 Other Options Considered

Reason ML

Top Pro

Uses the excellent Bucklescript Ocaml to Javascript transpiler

Top Con

A standard async syntax is pending

Async syntax is not standard across native/js projects and in both cases a bit awkward for non-ocaml devs. Currently this is reasonml most voted issue in their GitHub repo so hopefully, there's news soon. See More

Specs

Price:Free, Open source

Version:3.5.0

Top Pro

Aims to make the transition from Javascript easier

Despite being a completely different language Javascript programmer will find that the syntax of ReasonML has many familiarities with Javascript. See More

Top Pro

Uses established compiler technology from Ocaml with a tweaked syntax that leans more towards Javascript

Top Pro

Superior type inference

Ocaml type inference is so smart that you never have to repeat yourself and keep code very clean, type errors also are very pleasant See More

Top Pro

Compiles to JavaScript or assembly (ocaml)

The same reasonml code can compile to js (eg. run on browsers or node.js, use any lib in npm), or compile to assembly thru ocaml (unless of course you load js externals), running on any device, with C-comparable (or better) performance. See More

Top Pro

Immutability with escape hatches

reason includes true immutability, but it has escape hatches to let you use mutations in exceptional cases. See More

Top Pro

JSX syntax natively supoorted

reason was created by the creator of react, for developers already using JSX to template web or native UIs this results very familiar See More

Top Pro

Removes JavaScript "bad parts" but sticks to it's design philosophy

unlike other js-targetting languages that are thought as a way to have a language that pleases community X run in a browser, reason is really designed with JavaScript community in mind. it removes the bad parts but keeps its syntax and its best design principles (from Scheme): simplicity, minimalism, and functions as building block. See More

See All

ClojureScript

Top Pro

Live interactive programming with figwheel

Figwheel builds your ClojureScript code and hot loads it into the browser as you are coding! Every time you save your ClojureScript source file, the changes are sent to the browser so that you can see the effects of modifying your code in real time. See More

Top Con

Syntax may seem cryptic to people not used to Lisp

Lisp is sometimes called "syntax-less" and this is bewildering to those steeped in Algol-type syntax (Java, Javascript, C, etc). Being a dialect of Lisp, ClojureScript's syntax may seem cryptic and hard to understand for people not used to it. While Lisp has very little syntax compared to other languages and it's generally considered pretty terse, there's still an initial overhead in learning the language. See More

Webdev Tory Anderson's Experience

Lisp has a little learning curve because it is so different -- but the syntax is so minimal and elegant that writing becomes sheer joy. Add to the fact that there is superb tooling around Clojurescript (especially Figwheel) and you have a true winner. For me, the most rewarding part of working with all flavors of Clojure is the way they evolve your programming skills (Lisp enlightenment). See More

Specs

Site:https://clojurescript.org/

Price:Open Source

Current stable version:1.9

GZipped size:32 kB

Top Pro

Simple syntax

Lispness makes ClojureScript trivial to comprehend after an initial learning overhead. See More

Top Pro

Easy to use existing JavaScript libraries

Clojure and ClojureScript are designed to be able to interact with their host. So the language by design makes it is easy to use existing JS libraries. See More

Top Pro

Targets Google Closure-ready JavaScript for immense optimizations

Google's Closure Library converts regular JavaScript into a highly optimized form - including dead code analysis/elimination. It can even remove pieces of unused code from 3rd party libraries (eg, if you import jQuery but only use one function, Google Closure includes only that piece). See More

Top Pro

Share application logic between browser and Clojure server

Clojure is also able to run web servers, so one can reap similar benefits to NodeJS in terms of sharing code between client and server. See More

Top Pro

Can be used with React out of the box

Top Pro

Excellent build tools

Both Leiningen and Boot are great build tools that manage code dependencies and deployment. See More

Top Pro

Excellent tools for web development

ClojureScript has superb wrappers around React.js (see Reagent) that make building single-page apps a breeze. With figwheel, it's a web dev experience unlike any other -- hotloaded code, repl interaction, and instantly reflected changes make good development fun and fast. You can add things like Garden to make CSS-writing part of the same holistic experience and suddenly all development is a pleasant, smooth process. See More

Top Pro

The Spec core library

From the creator of Clojure: Spec is a new core library (Clojure 1.9 and Clojurescript) to support data and function specifications in Clojure. Writing a spec should enable automatic: Validation, Error reporting, Destructuring, Instrumentation, Test-data generation and Generative test generation. See More

See All

F#

Top Pro

Easier transition from other paradigms

Since F# is not a purely functional language, it lends itself to being more easily picked up by programmers that have experience with other paradigms. See More

Top Con

.NET's garbage collection is slow

Specs

Site:http://www.fsharp.org

Current stable version:4.1

License:Apache 2.0

IDE Support:Visual Studio, Code, Rider

Top Pro

Runs on the CLR

Since F# runs on the Common Language Runtime or CLR, it has access to the entire .NET Framework, as well as libraries written in other .NET languages such as C#, VB.NET, and C++/CLI. See More

Top Pro

Natively supported by Visual Studio

This is a .Net language natively supported by Visual Studio. Though it is not as tooled up as C# the support is still substantial. In particular, C# deployment scenarios can be enabled for it with small C# wrapper projects. See More

Top Pro

Concise syntax

F#'s syntax tends to be terse while remaining very readable and easy to understand without being a chore to write. See More

Top Pro

Built-in REPL

Makes it easy to write scripts and explore the language. See More

Top Pro

Allows to use the same language for web-frontend and server backend

Top Pro

Fable Javascript transpiler creates good readable javascript

Top Pro

Type Providers

Top Pro

F# is supported by Xamarin

Thanks to Xamarin, F# is a functional language that you can use to build for iOS, Android and Windows. See More

Top Pro

Fall into the pit of success

F# directs you into a workflow where the right way is the path of least resistance. Coming from a C# background, its restrictions might feel arbitrary at first (e.g., what do you mean my code has to be in dependency order!? Arbitrary alphabetical or bust!), but you'll soon realize that your code is cohesive, concise and consistent in a way that it never was before - and you can compile and run with confidence! See More

Top Pro

You can run F# in the browser

Thanks to a project like Fable, you can write and run your client app in F# and run it over JavaScript. It allows you to share code between your server and client. See More

Top Pro

Allows writing predictable code

Like many other functional languages, F# takes a stance of immutability for most of its constructs (state, values etc...). There are several reasons why having immutable values is good. One of those is that the code you are writing becomes much more predictable and you don't have to worry about any side effects. See More

Top Pro

Multiplatform, it runs on .Net Core

Forget Xamarin and Mono. F# now runs on the multiplatform .Net Core! See More

Top Pro

.NET Interoperability

Since F# runs on the Common Language Runtime or CLR, it has access to the entire .NET Framework, as well as libraries written in other .NET languages such as C#, VB.NET, and C++/CLI. See More

See All

Purescript

Top Pro

High performance FFI code

The Eff monad, which is used for FFI code, optimizes out calls to bind, and supports tail call optimization, resulting in clean, efficient Javascript. The psc compiler also specifically recognizes the ST monad, and transforms scoped variables into mutable Javascript variables, for even more efficient code. See More

Top Con

Lots of dependencies needed to get started

Purescript is written in Haskell, but meant to be used with Node.js. As a result, to get started , users must install ghc, cabal, node.js, grunt, and bower. Purescript also has its own compiler, and different semantics form Haskell, and so even after installing, there's still some overhead to getting productive with Purescript. See More

Top Pro

Type safety

Compiling should be your first unit test. A tight type system (static and hopefully strong) will catch many logic errors that are often difficult to spot through debugging. In languages like PureScript, if it compiles, it often runs properly. See More

Top Con

Slow compilation

On large project, for example Halogen See More

Top Pro

Pure functional language

You cannot have side effects, unless a function is explicitly defined as so. See More

Top Pro

Higher kinded types

Has Typeclasses and RankNTypes See More

Top Pro

Modules can be compiled to CommonJS

Modules compiled to CommonJS can be included with 'require', making it incredibly simple to call Purescript code from Javascript. See More

Top Pro

Has row polymorphism and extensible effects

Top Pro

FFI

FFI system is quite good and easy to use. You can import functions curried or not curried. Records and arrays use native JS objects and arrays. See More

Top Pro

Awesome web frameworks

Thermite (React) Halogen (VDOM, similar to ELM) And hit these up with Signals, Isolated/(Managed?) Components, powerful functions and FFI See More

Top Pro

Thorough documentation

The Purescript website has fairly thorough documentation for all of the language's features, and the Purescript blog contains several examples of practical usage. See More

See All

Scala

Top Pro

Immutable values

The immutable values make it perfect for working with concurrency. See More

Top Con

Can be intimidating for beginners

Scala is an industrial language. It brings functional programming to the JVM, but not with a "start small and grow the language" perspective, but rather a very powerful language for professional programmers. See More

Specs

Site:scala-lang.org

Price:Open Source (Free)

Current stable version:2.12.6

Top Pro

Multiparadigm

Scala supports both Functional and Object Oriented styles of programming. Beginners can learn both paradigms without having to learn a new language, and experts can switch between the two according to what best suits their needs at the time. See More

Top Con

JavaScript runtime seems immature

By the time of writing this, Scala doesn't seem quite usable on front-end since Scala.js didn't yet reach a release version. See More

Top Pro

Type inference

Scala offers type inference, which, while giving the same safety as Java's type system, allows programmers to focus on the code itself, rather than on updating type annotations. See More

Top Pro

Expressive functional programming abstraction for reusable and safe code

Top Pro

Compiles to JavaScript

Since we are talking about web frontends and because of the popularity of single page applications, Scala also compiles to JavaScript (search for Scala-JS). See More

Top Pro

Compiles to JVM bytecode

Aside from Java itself, Scala is by far the most popular of the many JVM languages. If you're developing for Android, or a similar JVM-only platform, or otherwise need out-of-the-box cross-platform compatibility, but the performance of a compiled language, Scala is the way to go. See More

See All

JavaScript

Top Pro

Native support in browser

Top Con

No syntactic or standard library support for value semantics

Especially unfortunate for those writing in a functional/value-oriented style is that JavaScript objects are compared by reference when using === and when performing lookups in arrays, maps, and sets. See More

Specs

Engine:V8/ChakraCore

Author:Ryan Dahl/Joyent

Minimum Supported ECMAScript Version:ECMAScript 6 (Node v4.x-v10.x)

ECMAScript Modules:Available (as a flag) (only on Node 8.x-10.x)

See All Specs

Top Pro

Required for web development

If you are looking to create web projects, you will have to learn Javascript in order to develop the client side code. If you learn the foundations of programming in JavaScript you can reapply that education later in building web applications. See More

Top Con

Limited standard library

Much often needed functionality is not in the standard library. (Contrast with Python.) However, there are well established libraries such as Lodash, to fill the gap (however, due to the diverse/fractured ecosystem it may not be clear what library to use). See More

Top Pro

First-class functions with lexical closures

While certainly not the only language with these features, this pro alone is so powerful that it compensates for most of JavaScript's problems. You'll learn to use closures and higher-order functions well in JavaScript, because you have to. And then you can generalize this knowledge to any other language that has these, and the good ones do. See More

Top Con

Asynchronous coding is not easy for beginners

JavaScript can work synchronously but its current use is mainly around asynchronous instructions, and it's surely not a good way to start learning programming. See More

Top Pro

Powerful syntactic support for value oriented programming

While writing in a mutable style is easy in JavaScript, writing in an immutable style has now become effortless with the advent of features such as Object Rest/Spread. These make it as easy, if not easier, to create new values as it is to modify existing one. Users of TypeScript or Flow that adopt this style further gain the advantage that they can omit almost all type annotations and still benefit from full analysis. See More

Top Con

Array-like objects

Many cases when you should get an Array, you just get an Array-like object instead and none of the Array methods work on it. See More

Top Pro

Speed (most implementations)

JS/ES is in the running for the fastest interpreted language given the optimizations and JIT integration of popular implementations. On the other hand, it fails utterly when compared with compiled (to native or VM code) languages. See More

Top Con

Weird type coercions

'5' - 1 == 4, but '5' + 1 == 51. There are other examples that make even less sense. See More

Top Pro

Modern ESNext is far better than the JS of days past

Modern JS has made great strides, and can be targerted to older (or non-standard) browsers using Babel. There are new language constructs that can make programming in JS comfortable.; e.g.: async / await ( <3 ). See More

Top Pro

Massive ecosystem

JavaScript has one of the largest programming ecosystems, as shown by the being the most popular language for projects on GitHub. As there are so many projects written in JavaScript there are lots of libraries available to build off of and many of them are written to be easy to use and integrate into other projects. There are also lots of resources available for learning JavaScript. Other than traditional tutorials, language learning sites such as Codecademy have JavaScript courses. The Mozilla Developer Database also serves as a great resource for learning about the standard libraries built into JavaScript. See More

Top Pro

Prototype based Object Oriented System

Being object oriented, it supports the predominate and powerful programming approach. Being prototype based, it provides an intuitive approach to OOP. Whereas other popular languages use classes, which focus on thinking in the abstract, Javascript's prototypes allow you to focus on thinking in the concrete. For example, in a prototypical language, you think of a rectangle, and define it. You now have a rectangle. Let's say you want a red rectangle, you copy the rectangle and give it the property red. Want a blue one? Copy rectangle again give it a blue. Big blue rectangle? Copy blue rectangle and make it big. In a class-based language, first you describe a rectangle, describe a red rectangle as a type of rectangle, describe blue and big blue rectangles, and now that you have described them, you must create instances of them, and only then do you have the rectangles. Essentially: Classes are factories for objects, prototypes are objects themselves, and the latter method was created to be more intuitive, which is particularly advantageous to beginners. See More

Top Pro

Great tools for development

Flow, JSHint/ESLint, Babel, npm, etc. See More

Top Pro

Can be very simple (teachable)

By setting a few ground-rules (effectively coding in a subset of JS), JS is one of the simplest languages to learn (requiring very few must-learn prerequisite concepts). See More

Top Pro

C-like syntax

After learning Javascript, you will feel at home in other languages as C-like syntax is very common. See More

Top Pro

JSON is native to JS

JSON is arguably a "must-learn". With JS, that's one less additional syntax to learn. See More

Top Pro

Atwood's Law "Any application that can be written in JavaScript, will eventually be written in JavaScript."

May also be a con. See More

Top Pro

Several Platforms to use the web stack and JS to create multi-platform apps

Opens the door to native application development as well as just websites. Use with React Native, Weex or Quasar (Vue), PhoneGap or Cordova, NativeScript... (etc) to build native apps. Use mostly the same code base for multi-platform and web. See More

Top Pro

High demand for JavaScript developers

If you're looking for a career as a developer, JavaScript is the place to focus your attention. There is a huge demand for good developers especially in frameworks such as React and Angular. See More

Top Pro

Instant gratification

While it's easy to argue that Python will give you instant gratification, JavaScript is far better in this regard. Make a small change to a page and it's immediately visible in the browser. You can throw in a JavaScript library like jQuery with minimal fuss. See More

Top Pro

Complete dev stack can be run online

With codepen.io and other prototyping tools, you can learn Javascript from a mobile device. You don't even need a computer. It can be learned from an internet cafe or public library. See More

Top Pro

Runs on both the browser and the server

With Node.js, it is now possible to run JavaScript as a web server. This would allow you to be able to create server based applications sooner than would if you had to learn a separate programming language as well for server side code. As JavaScript is the only language supported by web browsers it puts it in the unique situation of being the only programming language that's available on both the client side and server side. See More

Top Pro

Very good debugger

Has a built in debugger with break points, watches that work on local values, and a console that you can use to edit anything at any time. Both in the browser (eg: Chrome), and server (eg: Nodejs). See More

Top Pro

Easy to build an application

By using the UI capabilities in HTML and CSS you can develop substantial applications with graphical interfaces more quickly and with less effort than in other languages which would require you to learn a windowing library. Building a useful application is one of the best ways to learn a new language and because of the low learning curve for creating applications you can create more substatial programs and learn more practical programming priciple faster. See More

Top Pro

No installation required

If you run a web browser you already have JavaScript installed and can get started right away. Modern browsers such as Chrome also have very powerful programming consoles built into them. Aside from the browser console, you can also use online Javascript playgrounds such as JS Bin and JS Fiddle. Even from a tablet. See More

See All

Kotlin

Top Pro

Easy to share data classes between front end and back end

Multi platform project can compile the same Kotlin classes to JS and JVM See More

Specs

Site:http://kotlinlang.org

Price:Free, Open Source

Current stable version:1.3

Top Pro

Direct compile to JavaScript

The front end developed in Kotlin will be directly compiled into JavaScript. The same language can be used to develop front end, back end, DB access and build tool like Gradle. See More

Top Pro

Is built to solve industrial problems

Kotlin has been designed and built by developers who have an industrial background and not an academic one. As such, it tries to solve issues mostly found in industrial settings. For example, the Kotlin type system helps developers avoid null pointer exceptions. Reasearch languages usually do not have null at all, but APIs and large codebases usually need null. See More

Top Pro

Does not impose a particular philosophy of programming

It's not overly OOP like Java and it does not enforce strict functional paradigms either. See More

Top Pro

Officially supported for Android development

Starting with version 3.0 of Android Studio, Kotlin support will be built-in. This means that it's now easier than ever to use Kotlin for existing Android projects or even start writing Android apps only with Kotlin from scratch. This also means that Kotlin and Kotlin plugins for Android Studio will be fully supported in the future and their likelihood of being abandoned is quite small since Google is fully embracing the language for their Android ecosystem (alongside Java and C++). See More

Top Pro

Easy to learn if you have prior programming experience

Kotlin's syntax is extremely easy to understand. The language can be picked up in a few hours just by reading the language reference. See More

Top Pro

Great tooling support

Since Kotlin is made by Jetbrains (the developers of IntelliJ IDEA) so it stands to reason that the IntelliJ support for Kotlin is also great. Besides that, Kotlin also works well with existing Java tools such as Eclipse, Maven, Gradle, Android Studio, etc... See More

See All

OCaml

Top Pro

Supports multi-paradigm development

Ocaml is a very strong functional programming language but also supports some object oriented programmig technics See More

Top Con

Not very strong support for concurret / parallel development for the backend

This is in the moment meaningless for web frontend development. However it has relevance for the server backend development where concurrency is an advantage. Backends can definately be developed in Ocaml but lack of good concurrency support is a Con compared to other canguages. And as it is often adventurous to use the same language for frontend and backend, the impact needs to be considered. See More

Specs

Site:http://ocaml.org

Price:Open source (Free)

Current stable version:4.0.7

License:LGPL version 2.1

See All Specs

Top Pro

Encourages functional style

It steers you towards a functional style, but doesn't bother you with purity and "monads everywhere" like other languages, such as Haskell. See More

Top Con

Some small strange quirks in the syntax

It uses +. instead of + for floating point additions (and -. *. /. etc), which is easy to get used to, but it's not quite clear what it's supposed to be good for. See More

Top Pro

Uses one of the best transpilers

It comes with Bucklescript, which currently is one of the best Javascript transpilers. See More

Top Pro

Established technology

Top Pro

Strong editor integration

The merlin editor tool provides all you need to develop OCaml in your favourite editor. See More

Top Pro

One of the best for writing compilers

OCaml is compiled to native binary, so it's amazingly fast. Being a member of ML-family languages, it has expressive syntax for trees, and has great LLVM support. See More

Top Pro

Sophisticated and easy-to-use package manager

OPAM is a package manager for OCaml, which is really easy to use, just like npm. It creates a .opam folder in home directory. The documentation is great as well, and you can switch between multiple versions of OCaml for each project. You can also package your project and publish it on OPAM repositories, even if the dependencies do not exists on OPAM. See More

Top Pro

Easier transition from other programming languages

Ocaml supports functional but also object-oriented and procedural programming. See More

See All

Elixir

Top Pro

Great documentation

Elixir's documentation is very good. It covers everything and always helps solving any problem you may have. It's also always available from the terminal. See More

Specs

Site:https://elixir-lang.org

Price:Open source (Free)

Current stable version:1.8.1

GZipped size:3.61 MB (without required Erlang VM)

Top Pro

Great getting started tutorials

The tutorials are very clear and concise (even for a person not used to functional programming). Plus they are also very mobile friendly. See More

Top Pro

Scalability

Elixir programming is ideal for applications that have many users or are actively growing their audience. Elixir can easily cope with much traffic without extra costs for additional servers. More details can be found here. See More

Top Pro

Powerful metaprogramming

Write code that writes code with Elixir macros. Macros make metaprogramming possible and define the language itself. See More

Top Pro

Great for concurrency

Leverages the existing Erlang BEAM VM See More

Top Pro

Full access to Erlang functions

You can call Erlang functions directly without any overhead: https://elixir-lang.org/getting-started/erlang-libraries.html See More

Top Pro

Types don't get in the way

Top Pro

Easy to download libraries

Comes with built in build tool called "mix". This will automatically download libraries and put them in the scope of the application when you add them to the "deps" function and run mix deps.get See More

See All

Haste

Top Pro

Generates small, reasonably performant code

Haste generates a small amount of JavaScript which usually performs well. See More

Top Con

Lacks some minor Haskell functionality

Lacks support for Template Haskell for example. See More

Top Pro

Based on GHC frontend

So all syntax and type system extensions are supported. See More

Top Pro

Client and Server as the same application

Haste was designed to allow both the client and server to be written as parts of the same, type-safe application. This is in stark contrast to most other options, where the client and server are considered two separate entities, resulting in extra manual validation code and more chances for type errors. See More

Top Pro

Almost full power of Haskell

Haste supports the Haskell 2010 standard except for Template Haskell as well as most GHC extensions. See More

See All

Haskell

Top Con

Steep learning curve

Haskell lends itself well to powerful abstractions - the result is that even basic, commonly used libraries, while easy to use, are implemened using a vocabularly that requires a lot of backround in abstract mathematics to understand. Even a concept as simple as "combine A and B" is often, both in code and in tutorials, described in terms of confusing and discouraging terms like "monad", "magma", "monoid", "groupoid", and "ring". This also occasionally bears its ugly head in the form of complicated error messages from type inference. See More

Top Pro

Terse

Haskell is a very terse language, particularly due to its type inference. This means there's nothing to distract from the intent of the code, making it very readable. This is in sharp contrast to languages like Java, where skimming code requires learning which details can be ignored. Haskell's terseness also lends itself to very clear inline examples in textbooks, and makes it a pleasure to read through code even on a cellphone screen. See More

Specs

Site:https://www.haskell.org/

Paradigm:functional

Type System:static

Top Con

You have to learn more than just FP

Haskell is not only a functional language but also a lazy, and statically typed one. Not only that but it's almost necessary to learn about monads before you can do anything useful. See More

Top Pro

Mathematical consistency

As Haskell lends itself exceedingly well to abstraction, and borrows heavily from the culture of pure mathematics, it means that a lot more code conforms to very high-level abstractions. You can expect code from vastly different libraries to follow the same rules, and to be incredibly self-consistent. It's not uncommon to find that a parser library works the same way as a string library, which works the same way as a window manager library. This often means that getting familiar and productive with new libraries is often much easier than in other languages. See More

Top Con

Language Extensions lead to unfamiliar code

Haskell's language extensions, while making the language incredibly flexible for experienced users, makes a lot of code incredibly unfamiliar for beginners. Some pragmas, like NoMonomorphismRestriction, have effects that seem completely transparent in code, leading beginners to wonder why it's there. Others, like ViewPatterns, and particularly TemplateHaskell, create completely new syntax rules that render code incomprehensible to beginners expecting vanilla function application. See More

Top Pro

Highly transferable concepts

Haskell's referential transparency, consistency, mathematics-oriented culture, and heavy amount of abstraction encourage problem solving at a very high level, The fact that this is all built upon little other than function application means that not only is the thought process, but even concrete solutions are very transferable to any other language. In fact, in Haskell, it's quite common for a solution to simply be written as an interpreter that can then generate code in some other language. Many other languages employ language-specific features, or work around a lack of features with heavy-handed design patterns that discourage abstraction, meaning that a lot of what is learned, and a lot of code that is needed to solve a particular problem just isn't very applicable to any other language's ecosystem. See More

Top Con

Symbols everywhere

Haskell allows users to define their own infix operators, even with their own precedence. The result is that some code is filled with foreign looking operators that are assumed to be special-case syntax. Even for programmers who know they're just functions, operators that change infix precedence can potentially break expectations of how an expression is evaluated, if not used with care. See More

Top Pro

Referentially Transparent

Haskell's Purely Functional approach means that code is referentially transparent. This means that to read a function, one only needs to know its arguments. Code works the same way that expressions work in Algebra class. There's no need to read the whole source code to determine if there's some subtle reference to some mutable state, and no worries about someone writing a "getter" that also mutates the object it's called on. Functions are all directly testable in the REPL, and there's no need to remember to call methods in a certain order to properly initialize an object. No breakage of encapsulation, and no leaky abstractions. See More

Top Con

Delayed Results

Haskell's static typing, while helpful when building a project, can be positively frustrating for beginners. Quick feedback for errors means delaying the dopamine hit of code actually running. While in some languages, a beginner's first experience may be their code printing "Hello World" and then crashing, in Haskell, similar code would more likely be met with an incomprehensible type error. See More

Top Pro

Very few language constructs

The base language relies primarily on function application, with a very small amount of special-case syntax. Once you know the rules for function application, you know most of the language. See More

Top Con

Lazily Evaluated

Haskell's lazy evaluation implies a level of indirection - you're not passing a value, you're passing a thunk. This is often difficult to grasp not just for beginners, but for experienced programmers coming from strictly evaluated languages. This also means that, since for many, strict evaluation is their first instinct, initial expectations of a function's performance and complexity are often broken. See More

Top Pro

Quick Feedback

It's often said that, in Haskell, if it compiles, it works. This short feedback loop can speed up learning process, by making it clear exactly when and where mistakes are made. See More

Top Pro

Forces you to learn pure functional programming

It is pure and does not mix other programming paradigms into the language. This forces you to learn functional programming in its most pure form. This avoids you falling back on old habits and learn an entirely new way to program. See More

See All

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