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Rexx Is Still Strong After 25 years
therexxman writes "March marks the 25th anniversary of the Rexx programming language, and to celebrate the Rexx Language Association is hosting the 15th Annual Rexx Symposium at the IBM Research Labs in Boeblingen, Germany, from May 2 to 6, 2004.
Full details of the Symposium can be found in the 2004 Rexx Symposium Announcement.
Many of the world's 'Rexxperts' will be in attendance including Rexx's founder, Decimal Arithmetic guru, and IBM Fellow, Mike Cowlishaw."
For those that are wondering: REXX was created to be the universal command language for IBM mainframes. It is a replacement for the earlier command languages (EXEC? on VM and CLIST on MVS).
Then IBM ported it to OS/2, and from there it branched off. You can now find REXX for practically any platform. I have at least 5 different versions running on my Windows machine. (See Regina REXX on sourceforge, for example.)
REXX's main features include:
But the real key to REXX is it is designed so it can easily interface with multiple environments. For example, one REXX exec in z/OS can send commands and interact with MVS, TSO, ISPF, the ISPF Editor (as an Edit macro), and others.
The use of REXX on the mainframe is expanding. No mainframe product would think of writing their own command language; they just use REXX. And the more products you can interface with, the more useful it becomes.
Yes, I know there are Unix and other scripting languages that do the same types of things. But REXX is the standard for z/OS.
Other mainframe scripting languages were just disasters. I vividly remember replacing more than 1000 lines of EXEC-2 scripts with about 100 lines of REXX, and thinking that Mike Cowlishaw should be knighted.
:-)
And REXX beat ksh hands down in terms of power and readability as well.
I gave a speech ~ 1991 at a REXX Symposium about "REXX in UNIX". I had the crowd of mainframe and OS/2 people literally rolling in the aisles with laughter as I tried to explain ksh syntax to them. I made slides of some examples from the appendix in the KSH book, and it was hilarious. Even the geekiest UNIX geek has to admit that sh / ksh are disasters as programming languages. REXX was 10000% better.
On the other hand, as I pointed out in my speech that day, there was another new language coming up that was 20000% better. It was called Perl. Perhaps you've heard of it.
REXX was originally intended to be a scripting language simple enough to allow non-professional-programmers to use. None of the UNIX scripting languages, including Perl, hit that mark - but REXX does.
I haven't written any REXX in 10 years, and haven't missed it. But it WAS a big step forward, and should have been a better success.
REXX was very much like the Python or Perl of its day, in that it is a scripting language which can be used for everything from job control to add-on macros to interprocess communication.
It is a completely typeless language, more or less -- basically, everything is a string, so the same variable could hold "87", "eight-seven", "00110111", "0x0117", or "Four Score and Seven" -- and the interpreter kept track of what operations were meaningful (i.e., adding "4" and "5" would yield "9", but adding "4" and "Five" wouldn't). Not surprisingly, it had a wide variety of string manipulation functions built in -- ROT13 could easily be accomplished with one command ("translate()"), for instance.
On the other hand, it also featured arbitrary precision mathematics, which is a pretty nifty and not altogether common feature for a language.
It was fairly portable -- I wrote REXX code for OS/2 and the Amiga, and was usually able to move the code from one to the other without having to worry about anything more than CR/LF translation. I was able to make use of old mainframe REXX code too, although it was usually ALL IN CAPS and ugly, which isn't really REXX's fault.
In OS/2, I used REXX primarily as a batch language on steroids (the OS/2 "CMD" CLI ran REXX programs directly as a batch language), but I also used it to do some pretty heavy text manipulation as well. On the Amiga, I used REXX for those purposes, but the main things I used it for were for interprocess communication, and for extending the functionality of REXX-enabled programs. When Matt Dillon added a REXX port to his hacked-up version of emacs for the Amiga, I was able to use REXX macros to turn it from a nice programmer's text editor into one which did everything I wanted, excatly the way I wanted. I wrote macros to toss and filter FIDONet messages to and from my text editor.
The same power was available to the REXX ports on other Amiga programs, from word processors to graphics editors. As an aide to interprocess communication, it could be used to allow your graphics editor to control a raytracer, or for your text editor to use the spellchecker in your word processor.
I made some nice money at a time when I was underemployed by writing REXX programs to control the input and outputs of a NewTek Video Toaster for a guy with a mid-sized video production business; and the code was straightforward enough, and REXX easy enough to learn, that the business owner could easily make any minor changes to it himself (at the same time, after he had used it for a while, he was able to think of more and more things for it to do, which kept me in groceries for another month or two). For that matter, I also made a bit of money writing a REXX programming column for an Amiga magazine, so I really have fond memories of REXX for being a language that allowed me to continue, well, eating food.
For a long time, IBM tried to convince Microsoft to use REXX as the macro language for Office, instead of BASIC; needless to say, if they had succeeded, we would be living in a universal paradise of peace and understanding right now, or something like that.
Even today, I find myself thinking of all the neat things I could easily do with OpenOffice or AbiWord or Photoshop or Semware's text editor or Audacity or Zinf if they had REXX ports enabled...
You are looking for The Hessling Editor.
Jeff
I don't know anything about KEdit's "more" and "less" commands, but the "all" command to which he referred allows you to hide all the lines in a file that don't match a given expression. His 'all "if"' example tells the editor to show only the lines with "if" in them. The user can work with those lines, just as he always does, but without the distraction of the lines he's not currently interested in. It's one of the most popular features of the XEdit family of editors.
Jeff
Regina, the free implementation of Rexx, works at linux well. And it has documentation superior to anything from IBM ;)