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J is a pl 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 ''
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
NB. _?\d+
NB. _?\d+\.(?=\d+)
'Hello world'
Print() Debugging echo
Line Comments
NB. A comment
Semantic Indentation ϴ

Books about J from ISBNdb

title authors year publisher
Programming In C [Paperback] [Jan 01, 2011] DIXIT J B  J. B. Dixit Firewall
json5.html · j.html · fstar.html

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