Updated 2013-11-30 03:17:58 by escargo

J is a modern, freely-licensed descendant of APL

See Also  edit

SIGPLAN Chapter on Array Programming Languages
An APL playstation
rolled by RS. Need one Unicoded APL font, and Tk of course...
Tacit programming
some J code examples, and how to replay them in Tcl

Description  edit

I have only used APL but I understand J is a newer version that removes the need for the APL font which was always a bane of any installation. Yet, it seems strange for this to happen in the days of Unicode and graphics displays. I don't think it makes it any easier to read though.

For an example of of how to configure a unicode environment to get APL characters on your keyboard and have them display properly, see An APL playstation.

[There are many versions of J, the early versions are freely distributable in source, http://www.math.uwaterloo.ca/~ljdickey/#apl-j is a good resource. More recent versions are freely available only in binary form under a non-commercial license, http://www.jsoftware.com is the resource here. One thing which distinguishes J from other languages in the APL family is that Ken Iverson -- the guy who invented APL (to make it possible to document the IBM 360 architecture, back in the early 1960s) -- is also the architect behind J.]

Also of possible interest is a writeup on A [1] -- the implementation of A was important in getting J off the ground. Unfortunately, that page is a bit hard to read, because it expects that you have a special font installed with implied special character mappings -- they should have used gif images to represent those characters. Also, it's a bit old -- while that page claims that A+ "is is quite definitely not for sale", A+ is now distributed under the terms of the GPL.