Editing Erlang (programming language) (section)

{{Short description|Programming language}}
{{Use dmy dates|date=March 2020}}
{{Infobox programming language
| name = Erlang
| logo = Erlang logo.svg
| logo size = 140px
| paradigms = [[Multi-paradigm programming language|Multi-paradigm]]: [[Concurrent programming|concurrent]], [[Functional programming|functional]]
| family = 
| designer = {{unbulleted list|[[Joe Armstrong (programmer)|Joe Armstrong]]|Robert Virding|Mike Williams}}
| developer = [[Ericsson]]
| released = {{Start date and age|1986}}
| latest release version = {{wikidata|property|edit|reference|P348}}
| latest release date = {{start date and age|{{wikidata|qualifier|single|P348|P577}}}}
| typing = [[type system|Dynamic]], [[strong typing|strong]]
| scope = 
| implementations = Erlang
| dialects = 
| influenced_by = [[Lisp (programming language)|Lisp]], [[PLEX (programming language)|PLEX]],<ref>{{cite web |url=https://vimeo.com/97329186 |title=Joe Armstrong - Functional Programming the Long Road to Enlightenment: a Historical and Personal Narrative |first=N. D. C. |last=Conferences |date=4 June 2014 |publisher=Vimeo}}</ref> [[Prolog]], [[Smalltalk]]
| influenced = [[Akka (toolkit)|Akka]], [[Clojure]],<ref>{{cite web|url=http://radar.oreilly.com/2011/06/clojure-java-lisp-jvm.html|website=radar.oreilly.com|title=Clojure: Lisp meets Java, with a side of Erlang - O'Reilly Radar}}</ref> [[Dart (programming language)|Dart]], [[Elixir (programming language)|Elixir]], [[F Sharp (programming language)|F#]], [[Opa (programming language)|Opa]], [[Oz (programming language)|Oz]], [[Reia (programming language)|Reia]], [[Rust (programming language)|Rust]],<ref>{{Cite web |url=https://doc.rust-lang.org/reference/influences.html |title=Influences - The Rust Reference |website=The Rust Reference |access-date=2023-04-18}}</ref> [[Scala (programming language)|Scala]], [[Go (programming language)|Go]]
| file ext = .erl, .hrl
| license = [[Apache License 2.0]]
| website = {{url|https://www.erlang.org}}
| wikibooks = Erlang Programming
}}

'''Erlang''' ({{IPAc-en|ˈ|ɜr|l|æ|ŋ}} {{respell|UR|lang}}) is a [[General-purpose programming language|general-purpose]], [[concurrent computing|concurrent]], [[Functional programming|functional]] [[High-level programming language|high-level]] [[programming language]], and a [[Garbage collection (computer science)|garbage-collected]] [[runtime system]]. The term Erlang is used interchangeably with Erlang/OTP, or [[Open Telecom Platform]] (OTP), which consists of the Erlang [[runtime system]], several ready-to-use components (OTP) mainly written in Erlang, and a set of [[Systems architecture|design principles]] for Erlang programs.<ref>{{cite web |url=http://erlang.org/doc/system_architecture_intro/sys_arch_intro.html#id58791 |title=Erlang – Introduction |website=erlang.org |access-date=6 February 2017 |archive-date=8 September 2019 |archive-url=https://web.archive.org/web/20190908105859/http://erlang.org/doc/system_architecture_intro/sys_arch_intro.html#id58791 |url-status=dead }}</ref>

The Erlang [[runtime system]] is designed for systems with these traits:

*[[Distributed computing|Distributed]]
*[[Fault tolerance|Fault-tolerant]]
*[[Soft real-time]]
*[[High availability|Highly available]], [[Uptime|non-stop]] applications
*[[Hot swapping#Software|Hot swapping]], where code can be changed without stopping a system.<ref>{{cite web |last1=Armstrong |first1=Joe |last2=Däcker |first2=Bjarne |last3=Lindgren |first3=Thomas |last4=Millroth |first4=Håkan |title=Open-source Erlang – White Paper |url=http://ftp.sunet.se/pub/lang/erlang/white_paper.html|archive-url=https://web.archive.org/web/20111025022940/http://ftp.sunet.se/pub/lang/erlang/white_paper.html |archive-date=25 October 2011 |access-date=31 July 2011}}</ref>

The Erlang [[programming language]] has [[Immutable object|immutable]] data, [[pattern matching]], and [[functional programming]].<ref>Hitchhiker’s Tour of the BEAM – Robert Virding http://www.erlang-factory.com/upload/presentations/708/HitchhikersTouroftheBEAM.pdf</ref> The sequential subset of the Erlang language supports [[eager evaluation]], [[single assignment]], and [[dynamic typing]].

A normal Erlang application is built out of hundreds of small Erlang processes.

It was originally [[proprietary software]] within [[Ericsson]], developed by [[Joe Armstrong (programmer)|Joe Armstrong]], Robert Virding, and Mike Williams in 1986,<ref name="hopl">{{cite conference |last=Armstrong |first=Joe |title=History of Erlang |work=HOPL III: Proceedings of the third ACM SIGPLAN conference on History of programming languages |date=2007 |isbn=978-1-59593-766-7}}</ref> but was released as [[free and open-source software]] in 1998.<ref>{{cite web|url=http://www.cio.com/article/3020454/open-source-tools/how-tech-giants-spread-open-source-programming-love.html|title=How tech giants spread open source programming love - CIO.com|date=8 January 2016|access-date=5 September 2016|archive-date=22 February 2019|archive-url=https://web.archive.org/web/20190222070551/https://www.cio.com/article/3020454/open-source-tools/how-tech-giants-spread-open-source-programming-love.html|url-status=dead}}</ref><ref>{{cite web |url=http://www.erlang.se/onlinenews/ErlangOTPos.shtml|archive-url=https://web.archive.org/web/19991009002753/http://www.erlang.se/onlinenews/ErlangOTPos.shtml|url-status=dead|archive-date=9 October 1999 |title=Erlang/OTP Released as Open Source, 1998-12-08}}</ref> Erlang/OTP is supported and maintained by the Open Telecom Platform (OTP) product unit at [[Ericsson]].