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

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Try now: Riju · TIO

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...

Example from Riju:
echo 'Hello, world!'
Example from hello-world:
#!/opt/local/bin/jc echo 'Hello World' exit ''
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 Token Example
NB. _?\d+
NB. _?\d+\.(?=\d+)
Strings '
'Hello world'
Print() Debugging echo
Line Comments NB.
NB. A comment
Semantic Indentation X

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