#What is AREXX?
10 messages in this thread
What exactly is AREXX, and what is the advantage of having an AREXX port? Am
looking for answers or even some direction in finding them…
pm
[B
ARexx is a standardized method for different programs to communicate with
each other. Currently, all programs can open public ports with which to
communicate to other programs, including Intuition, however there exists no
standard way of passing information back and forth. Thus, usually its only used
by programs of the same manufacturer.
ARexx is also a programming language, derived from Rexx on IBM mainframes,
which is fully featured and allows you to manipulate all the ports by program.
Thus, you could write a program to open a text editor, have it load a file and
do a search and replace on it, just by executing one program from the CLI.
Nag Plus/TxEd/MaxiPlan have unified each other. When Nag Plus finds that
its time to inform the user of an upcoming event, it can not only do its thing,
but it will automatically open TxEd to an appropriate document and search for
corresponding information in a Maxiplan spreadsheet.
What are the advantages to owning ARexx? You can write your own programs
and use others instead of just using the features within an Arexx supporting
program. Without ARexx, you can still use it within programs which already
contain arexx.
— Ethan
AREXX is everything Ethan says. At a more basic level most people use it as
(a) a macro language for supporting programs (as opposed to having multiple
programs talk to each other) and (b) a super duper batch (CLI script) language.
Example of (a): I have an address database in MicroFiche Filer +. I wrote a
AREXX macros for it that makes it an autodialer, prints out mailing labels, or
prints out my phonebook.
Example of (b): Larry Philips has written a helpful script that automatically
puts an entire subdirectory of files into an ARChive, doing renames to match
the name length limits of ARC. Larry's script also creates a (non-AREXX) batch
file to restore the original names when the file is unARCed. I've written a
script that recursively searches all subdirectories and adds a drawer icon if
one doesn't already exist.
AREXX is about as tough to learn as BASIC. It is an interpreted language but
the interpreter "lives" in the system so you use it from anything that has an
AREXX port or the CLI. — Art
ARexx is MUCH harder than BASIC. The rules governing its operation are
hardly straightforward, the function are many and VERY varied and the whole
concept is much more complicated. I know BASIC, Pascal, FoxBase and am roughly
familiar with C and Amiga Machine Language and I can barely follow the ARexx
manual. The manual however is only reference, and a good tutorial/instruction
guide might help a lot.
— Ethan
Ethan,
I would have to disagree that ARexx is harder to learn/use than Basic. I do
agree that the manual is not one that is conducive to learning it for most
folks though.
-larry
But Larry, I know you are a programmer! BASIC is really intuitive
(somewhat). You don't have to worry about con: to open a window, for example.
Just use the window commmand. How about menus and gadgets!
— Ethan
Ethan,
Windows are no more difficult in ARexx than they are in Basic. The syntax is
just different, is all. Menus and gadgets are not part of ARexx, but are added
externally with functions libraries or programs written specifically for those
functions. Calling external library functions is easier, if anything, in ARexx
than it is in Basic. Rememebr, ARexx itself doesn't do a lot of things, and if
those things need to be available to you, then it is probably the wrong
language. Note that this is no different than any language.
Look at typing of variables. In Arexx you can assign strings, characters, or
numbers to variables without having to worry about what the variable 'type' is.
Virtually all other languages (except assembler and Icon), require at least
some attention to variable types.
I really think people 'get used to' Basic, and become afraid of anything that
isn't actually Basic. I also think that a lot of this fear will go away when
ARexx is included with the system
-larry
Ethan, I learned a lot by looking and playing with some of the ARexx programs
in the Libs here. Almost all the functions are demonstrated and somehow when
you see them work (the trace option) it starts to make better sense. Rob.
Bill's reference manual that accompanies AREXX is just that, a reference
manual. He does attempt to show you how to use REXX, but I (and Bill)
recommend a book by M.F. Cowlishaw, the originator of REXX. It is full of
excellent examples, discussions of some of the design decisions involved in the
original definition of REXX, and its early history. It's in softcover,
published by Prentice-Hall, ISBN 0-13-780735-X. I recommend it very highly!
I just noticed that I stupidly (some kind of brain check) forgot to give the
title of Cowlishaw's book: "The REXX Language, A Practical Approach to
Programming". …. And I thought my Alzheimer's was in remission. Oh, well.