Currently J is on version 903, and soon 904. On the jsoftware.com website, versions all the way back to J602 are installable.
There is no backward compatibility, so old scripts often only run on specific versions of J. It would be good to have an environment manager, which can manage the installation and update of each J Version, and become aware when a new J Version is released. Each J version has its own package manager, but it would be useful to have an actual environment manager (GUI would be good). I created a very rudimentary shell script (for Linux only). https://github.com/jonghough/jman which will create an empty project, for a given J version, and install the J version if it is not already installed on the user's machine. Thanks, Jon ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
