crystal.scroll

import ../code/conceptPage.scroll

id crystal
name Crystal
appeared 2014
creators Ary Borenszweig and Juan Wajnerman and Brian Cardiff
tags pl
website https://crystal-lang.org
blog https://crystal-lang.org/blog/
releaseNotes https://github.com/crystal-lang/crystal/blob/master/CHANGELOG.md
latestVersion 1.12.1
webRepl https://play.crystal-lang.org/#/cr

isOpenSource true
writtenIn crystal ecr yaml markdown html javascript powershell bourne-shell css c svg make xml python json z-shell bash cpp nix ini
tryItOnline crystal
fileExtensions cr
clocExtensions cr
fileType text
wordRank 2716
documentation https://crystal-lang.org/reference/1.6/index.html
documentation https://devdocs.io/crystal/
faq https://forum.crystal-lang.org/
rosettaCode http://www.rosettacode.org/wiki/Category:Crystal
centralPackageRepositoryCount 0
repoStats
 firstCommit 2012
 commits 16193
 committers 638
 files 2304
 newestCommit 2024
country Argentina and Germany and Turkey
originCommunity https://forum.crystal-lang.org/
projectEuler Crystal
 memberCount
  2019 5
  2022 14

helloWorldCollection Crystal
 # Hello world in Crystal
 
 puts "Hello World"
pygmentsHighlighter Crystal
 filename crystal.py
 fileExtensions cr
rijuRepl https://riju.codes/crystal
 example
  puts "Hello, world!"
  
 description General-purpose, object-oriented programming language with syntax inspired by the language Ruby
 fileExtensions cr
 website https://crystal-lang.org/
 gitRepo https://github.com/crystal-lang/crystal
subreddit https://reddit.com/r/crystal_programming
 memberCount
  2022 4118
twitter https://twitter.com/crystallanguage
leachim6 Crystal
 filepath c/Crystal.cr
 fileExtensions cr
 example
  puts "Hello World"
  
gource https://www.youtube.com/watch?v=YToY_0fhEzc
languageServerProtocolProject https://github.com/kofno/scry
 writtenIn crystal
compilerExplorer Crystal
 example
  # Type your code here, or load an example.
  
  # compile with --prelude=empty
  fun square(num : Int32) : Int32
    num &* num
  end

keywords abstract do if nil? self unless alias else in of sizeof until as elsif include out struct when as? end instance_sizeof pointerof super while asm ensure is_a? private then with begin enum lib protected true yield break extend macro require type case false module rescue typeof class for next return uninitialized def fun nil select union
githubRepo https://github.com/crystal-lang/crystal
 stars 17909
 forks 1367
 subscribers 416
 created 2012
 updated 2022
 firstCommit 2012
 description The Crystal Programming Language
 issues 1520

lineCommentToken #
printToken puts
stringToken "
booleanTokens true false
includeToken require

hasTypeInference true
hasLineComments true
 # A comment
hasComments true
 # A comment
hasMultiLineComments false
hasPrintDebugging true
hasSemanticIndentation false
hasStrings true
 "Hello world"
hasBooleans true
hasImports true
 require "../../spec_helper"
hasClasses true
hasFunctions true
hasConditionals true
hasWhileLoops true

wikipedia https://en.wikipedia.org/wiki/Crystal_(programming_language)
 example
  channel = Channel(Int32).new
  
  spawn do
    puts "Before first send"
    channel.send(1)
    puts "Before second send"
    channel.send(2)
  end
  
  puts "Before first receive"
  value = channel.receive
  puts value # => 1
  
  puts "Before second receive"
  value = channel.receive
  puts value # => 2
 related ia-32 freebsd ruby c rust go csharp python llvmir csp
 summary In computer software programming languages, Crystal is a general-purpose, object-oriented programming language, designed and developed by Ary Borenszweig and Juan Wajnerman and more than 200 contributors. With syntax inspired by the language Ruby, it is a compiled language with 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. Crystal is in active development. It is released as free and open-source software under the Apache License version 2.0
 pageId 48972626
 dailyPageViews 143
 created 2016
 backlinksCount 31
 revisionCount 95
 appeared 2014
 fileExtensions cr

tiobe Crystal
 currentRank 24

domainName crystal-lang.org
 registered 2013
 awisRank
  2022 387907
  2017 299324

githubBigQuery Crystal
 repos 1197
 users 767

linguistGrammarRepo https://github.com/atom-crystal/language-crystal
 firstCommit 2013
 lastCommit 2018
 committerCount 47
 commitCount 320
 sampleCount 3
 example
  #!/usr/bin/env bin/crystal --run
  require "../../spec_helper"
  
  describe "Type inference: declare var" do
    it "types declare var" do
      assert_type("a :: Int32") { int32 }
    end
  
    it "types declare var and reads it" do
      assert_type("a :: Int32; a") { int32 }
    end
  
    it "types declare var and changes its type" do
      assert_type("a :: Int32; while 1 == 2; a = 'a'; end; a") { union_of(int32, char) }
    end
  
    it "declares instance var which appears in initialize" do
      result = assert_type("
        class Foo
          @x :: Int32
        end
  
        Foo.new") { types["Foo"] }
  
      mod = result.program
  
      foo = mod.types["Foo"] as NonGenericClassType
      foo.instance_vars["@x"].type.should eq(mod.int32)
    end
  
    it "declares instance var of generic class" do
      result = assert_type("
        class Foo(T)
          @x :: T
        end
  
        Foo(Int32).new") do
          foo = types["Foo"] as GenericClassType
          foo_i32 = foo.instantiate([int32] of Type | ASTNode)
          foo_i32.lookup_instance_var("@x").type.should eq(int32)
          foo_i32
      end
    end
  
    it "declares instance var of generic class after reopen" do
      result = assert_type("
        class Foo(T)
        end
  
        f = Foo(Int32).new
  
        class Foo(T)
          @x :: T
        end
  
        f") do
          foo = types["Foo"] as GenericClassType
          foo_i32 = foo.instantiate([int32] of Type | ASTNode)
          foo_i32.lookup_instance_var("@x").type.should eq(int32)
          foo_i32
      end
    end
  
    it "declares an instance variable in initialize" do
      assert_type("
        class Foo
          def initialize
            @x :: Int32
          end
  
          def x
            @x
          end
        end
  
        Foo.new.x
        ") { int32 }
    end
  end
  

isbndb 0

githubLanguage Crystal
 fileExtensions cr
 trendingProjects
  author name avatar url language languageColor stars forks currentPeriodStars description
  omarroth invidious https://github.com/omarroth.png https://github.com/omarroth/invidious Crystal #000100 1184 86 154 "Invidious is an alternative front-end to YouTube"
  crystal-lang crystal https://github.com/crystal-lang.png https://github.com/crystal-lang/crystal Crystal #000100 13807 1071 172 "The Crystal Programming Language"
 trendingProjectsCount 3
 type programming
 interpreters crystal
 aceMode ruby
 codemirrorMode crystal
 codemirrorMimeType text/x-crystal
 tmScope source.crystal
 repos 7522

stackOverflowSurvey
 2021
  users 466
  medianSalary 72400
  fans 790
  percentageUsing 0.01

semanticScholar 0