J - Programming language

J is an open source programming language created in 1990 by Kenneth E. Iverson and Roger Hui.

#108on PLDB

34Years Old

468Repos

Download source code:

git clone https://github.com/jsoftware/jsource

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The J programming language, developed in the early 1990s by Kenneth E. Iverson and Roger Hui, is a synthesis of APL (also by Iverson) and the FP and FL function-level languages created by John Backus. To avoid repeating the APL special-character problem, J uses only the basic ASCII character set, resorting to the use of the dot and colon as inflections to form short words similar to digraphs. Read more on Wikipedia...

Tags: programming language, arrayLang
J is developed on GitHub and has 650 stars
Watch the history of the J repo visualized with Gource
There are at least 468 J repos on GitHub
Early development of J happened in Jsoftware Inc
J is written in C, Assembly language, Bourne shell, Make, XML, Markdown, YAML, C++, IDL, HTML
The Google BigQuery Public Dataset GitHub snapshot shows 124 users using J in 151 repos on GitHub
There are 2,478 Project Euler users using J
Explore J snippets on Rosetta Code
J on HOPL
J appears in the TIOBE Index
Pygments supports syntax highlighting for J
GitHub supports syntax highlighting for J
There is 1 Jupyter Kernel for J
jsoftware.com was registered in 1996
See also: (13 related languages) Linux, APL, FP, FL, NumPy, SuperCollider, ASCII, Unix, SQL, C, Unicode, K, Q
Read more about J on the web: 1.
4 PLDB concepts link to J: Goal, Jelly, U, Uiua

Example from Riju:

echo 'Hello, world!'

Example from hello-world:

#!/opt/local/bin/jc
echo 'Hello World'
exit ''

Example from the Hello World Collection:

NB. Hello World in J
'Hello World' 1!:2(2)

Example from Linguist:

#!/bin/jconsole
echo 'Hello, GitHub!'
exit ''

Example from Wikipedia:

3 |. 1 0 1 1 0 0 1 1 1 1 1             NB. rotate
1 0 0 1 1 1 1 1 1 0 1

Language features

Feature	Supported	Example	Token
Integers	✓	NB. _?\d+
Floats	✓	NB. _?\d+\.(?=\d+)
Strings	✓	'Hello world'	'
Print() Debugging	✓		echo
Line Comments	✓	NB. A comment	NB.
Comments	✓
Semantic Indentation	X