                                 
                                 
                                 
                                 
                                 
                                 
                                 
                                 
                                 
                                 
                                 
                                 
                                 
                                 
                                 
                                 
                           J  POSTINGS
                                 
                       from the messages of
                                 
                  USENET newsgroup comp.lang.apl
                                 
                               and
                                 
               BITNET/EARN APL-List (mailing list)
                                 
                                 
                                 
                                 
                                 
                                 
                                 
                                 
                                 
                                 
                                 
                                 
                                 
                                 
                                 
                                 
                                 
                                 
                            edited by:
                                 
                          A. P. DELMOTTE
                      AGRTQB@IRMFAO01.BITNET
                                 
                               and 
                                 
                           S. W. SIRLIN
                    SAM@KALESSIN.JPL.NASA.GOV
                                 
                                 
                                 
                                 
                                 
                    Louvain-la-Neuve June 1992
                                 

                           INTRODUCTION

The following pages about the new programming language "J" are a
compilation of the messages which appeared on the network during
1990 and 1991.

During the preparation of the APL92 conference (St Petersburg,
July 1992), I started to collate and clean the messages of the
newsgroup and mailing list. Being interested in J, I started to
set apart the messages concerning J. Rapidly I realized that
there was a lot of information which would be more or less lost
if it were not presented as a whole; the messages are archived
and can be retrieved, but they are mixed with much other
information.

Furthermore the messages followed the evolution of the language
and would be difficult to use by someone starting in the middle
of the discussions. It was then necessary to edit them and bring
them to a unique version of the language. 

I felt unable to tackle this task - my knowledge of J (and APL)
being too rudimentary - and asked for help from Sam Sirlin and
Raul Rockwell, two major contributors to the discussions. Both
responded positively and we started to exchange files containing
the material to be edited (this brought some problems which we
solved with xxencoding and modified uuencoding).

We chose to bring everything to version 4.1; the language is
still evolving but the changes are less important than the ones
which took place at the beginning.

Unfortunately Raul, overloaded by work, has not been able to
carry on the work so Sam did all the editing and I prepared the
final presentation. All the mistakes and incorrections remaining
in the text are then mine.

The text is presented as it appeared on the network, with some
comments added. This makes it sometimes difficult but it retains
the style of each author, which we felt was important. The
messages have been assembled by subject and grouped in somewhat
arbitrary chapters according to the theme discussed and to the
difficulty.

As such we hope it will serve as an introduction to the language
and fill the gap in documentation existing at present.

I want to thank Sam for his help and enormous and excellent
editing and Raul for his readiness to participate the task.

                                                   Alain Delmotte
 