Crystal (programming language): Difference between revisions

Revision as of 00:40, 23 March 2021

Latest revision as of 13:28, 3 April 2025

(45 intermediate revisions by 28 users not shown)

Line 1:

{{AboutShort description|theObject-oriented [[programming language]]||Crystal (disambiguation)}}

{{Infobox programming language

| name = Crystal

| logo = Crystal language logo.svg

| paradigm = [[Multi-paradigm programming language|Multi-paradigm]]: [[Object-oriented programming|object-oriented]], [[Concurrent computing|concurrent]]

| released = {{Start date and age|2014|06|1819}}<ref>{{factCite web|url=https://crystal-lang.org/2014/06/19/crystal-0.1.0-released.html|title=Crystal 0.1.0 released!|website=crystal-lang|date=January19 June 2014 2021}}</ref>

| designer = Ary Borenszweig, Juan Wajnerman, Brian Cardiff

| developer = Manas Technology Solutions

| latest release version = {{wikidata|property|referencepreferred|references|edit|P348|P548=Q2804309|P348}}

| latest release date = {{startStart date and age|{{wikidata|qualifier|preferred|single|P348|P548=Q2804309|P348|P577}}|df=yes}}

| typing = [[Type system#Static type checking|static]], [[Type system#Inferred type checking|inferred]], [[Type system#structuralNominal type system|structuralnominal]], [[Duck_typing|duck]]

| influenced by = [[Ruby (programming language)|Ruby]], [[C (programming language)|C]], [[Rust (programming language)|Rust]], [[Go (programming language)|Go]],<ref name="rel_0.18.0"/>go [[C Sharp (programming language)|C#]],<ref name=multithread"rel_0.18.0"/> [[Python (programming language)|Python]]<ref name="rel_0.18.0"/>

| programming language = Crystal

| platform = [[IA-32]] (i386), [[x86-64]], [[AArch64]]<ref name="platform-support" />

| operating system = [[Linux]], [[macOS]], [[FreeBSD]], [[OpenBSD]], [[Microsoft Windows|Windows]]<ref name="platform-support" />

| license = [[Apache License 2.0]]

| file ext = .cr

| website = {{URL|https://crystal-lang.org}}}}

}}

'''Crystal''' is a [[high-level programming language|high-level]] [[general-purpose programming language|general-purpose]], [[object-oriented programming]] language, designed and developed by Ary Borenszweig, Juan Wajnerman, Brian Cardiff and more than 300400 contributors.<ref name="contributors" /> With syntax inspired by the language [[Ruby (programming language)|Ruby]],<ref name="rel_0.18.0"/> it is a [[compiled language]] with [[Type system#Static type checking|static type-checking]], but specifying the types of variables or method arguments is generally unneeded. Types are resolved by an advanced global [[type inference]] algorithm.<ref name="type-inference-i" /><ref name="devm" /> Crystal

is currently in active development. It is released as [[free and open-source software]] under the [[Apache License]] version 2.0.

Line 26 ⟶ 24:

Work on the language began in June 2011,<ref name="story"/> with the aim of merging the elegance and productivity of Ruby with the speed, efficiency, and type safety of a compiled language.<ref name="why_crystal"/><ref name="story"/> Initially named ''Joy'', it was quickly renamed to ''Crystal''.<ref name="story"/>

The Crystal compiler was first written in Ruby, but later rewritten in Crystal, thus becoming [[Self-hosting (compilers)|self-hosting]], {{as of |November 2013|lc=true}}.<ref name="goodbye_ruby"/> The first official version was released in June 2014.<ref name="rel_0.1.0"/> In July 2016, Crystal joined the [[TIOBE index]].

== Description ==

Although resembling the Ruby language in syntax, Crystal compiles to much more efficient native code using an [[LLVM]] backend, at the cost of precluding the dynamic aspects of Ruby. However, theThe advanced global type inference used by the Crystal compiler, combined with the use of [[union type]]s, gives Crystalit more the feel of a higher-level scripting language more so than many other comparable programming languages. The languageIt has automated garbage collection and currently offers a [[Boehm garbage collector|Boehm collector]]. Crystal possesses a macro system and supports generics as well as both method and operator overloading. Crystal'sIts concurrency model is inspired by [[communicating sequential processes]] (CSP) and implements light-weightlightweight fibers and channels (for communicatinginterfiber between fiberscommunication), inspired by [[Go (programming language)|Go]].<ref name = "rel_0go multithread">{{cite web | url=https://forum.18crystal-lang.0"org/t/crystal-multithreading-support/6622/19 | title=Crystal multithreading support | date=23 February 2024 }}</ref>

== Examples ==

=== Hello World ===

This is the simplest way to write the [["Hello, World!" program|Hello World]] program in Crystal:

<syntaxhighlight lang="crystal">

Line 62 ⟶ 60:

server = HTTP::Server.new do |context|

context.response.content_type = "text/plain"

context.response.print "Hello world! The time is #{Time.nowlocal}"

end

Line 90 ⟶ 88:

<syntaxhighlight lang="crystal">

desired_things = [:unicorns, "butterflies", 1_000_000]

p typeof(desired_things.first) # typeof returns the compile time type, here (Int32Symbol | String | SymbolInt32)

p desired_things.first.class # the class method returns the runtime type, here Symbol

</syntaxhighlight>

Line 115 ⟶ 113:

puts value # => 2

</syntaxhighlight>

== Adoption ==

In 2020, it was reported that the infotainment units in vehicles produced by [[Nikola Corporation]] were written in Crystal.<ref>{{cite web |last1=Pettinati |first1=Martin |title=Nikola Motor Company: Crystal powered dashboards on the trucks of the future {{!}} Manas.Tech |url=https://manas.tech/blog/2020/02/11/nikola-motor-company/ |website=Manas Technology Solutions |language=en |date=11 February 2020}}</ref> Much of the backend of the [[Kagi (search engine)|Kagi search engine]] is written with Crystal.<ref>{{cite web |title=Zac Nowicki – Tales from Kagi {{!}} CrystalConf 2023 |url=https://www.youtube.com/watch?v=r7t9xPajjTM |date=13 November 2023}}</ref>

== Further reading ==

Line 129 ⟶ 131:

| isbn = 978-1-68050-286-2

| url = https://pragprog.com/book/crystal/programming-crystal

}}

* {{citation

| first1 = George

| last1 = Dietrich

| first2 = Guilherme

| last2 = Bernal

| date = May 27, 2022

| title = Crystal Programming

| publisher = [[Packt Publishing]]

| isbn = 978-1801818674

}}

* {{citation

Line 137 ⟶ 149:

| trans-title = The Ruby-like programming language Crystal

| work = [[Linux Magazine|Linux Magazin]]

| issue = 033/2016

| issn = 1432-640X

| language = de

Line 148 ⟶ 160:

<ref name="platform-support">

{{cite web

| url = https://github.com/crystal-lang.org/crystalreference/wiki/Platform-Supportplatform_support.html

| title = Crystal Platform Support

| work website = Crystal Wikicrystal-lang.org

| via = [[GitHub]]

}}

</ref>

Line 161 ⟶ 172:

| via = [[GitHub]]

}}

</ref>

</ref>

<ref name="type-inference-i">

Line 195 ⟶ 205:

<ref name="why_crystal">

{{cite web

| url = httphttps://motion-expressadlerhsieh.com/blogp/why-use-crystal-lang

| title = Why Crystal programming language?

| last = Hsieh

| first = Adler

| date = September 20, 2015

| website = motion-expressadlerhsieh.com

}}

</ref>

Line 221 ⟶ 231:

| date = June 16, 2016

| website = crystal-lang.org

| quote =

| quote = It's heavily inspired by Ruby, and other languages (like C#, Go and Python).

}}

</ref>

<ref name="devm">

{{cite web

| url = https://devm.io/ruby/crystal-ruby-programming

| title = Programming with Crystal: 'A language for humans and computers'

| date = July 3, 2023

| website = devm.io

}}

</ref>

Line 228 ⟶ 246:

== External links ==

* {{Official website|crystal-lang.org}}

* [https://crystal-lang.org/reference/ Documentation]

* {{Github|crystal-lang}}

* [https://reddit.com/r/crystal_programming /r/crystal_programming subreddit]

* [https://crystal-ann.com Crystal Announcements]

[[Category:Programming languages]]

[[Category:Multi-paradigm programming languages]]

[[Category:Object-oriented programming languages]]

[[Category:ProgrammingConcurrent programming languages created in 2014]]

[[Category:Software using the Apache license]]

[[Category:Statically typed programming languages]]

[[Category:Cross-platform free software]]

[[Category:Cross-platform software]]

[[Category:Free and open source compilers]]

[[Category:Software using the Apache license]]

[[Category:Programming languages created in 2014]]

[[Category:2014 software]]