Saul Jaffe
Rutgers University
ARPA: Jaffe@Rutgers
UUCP: caip!jaffe
Dyalog might have a WSIS receiver, because surely they have faced this
problem before. (A number of people are moving to Dyalog.) At least
two progressive APL's include WSIS as a built in utility, and maybe
Dyalog is one of them, I can not remember. If they do not have it yet,
this is a good time to negotiate for it!
It is not hard to write a WSIS sender. If you also have to write your
own receiver, you can simplify the WSIS conventions because you know
exactly what the atomic vector is on each machine.
There are a couple of places to look for WSIS documentation. If I
remember correctly, it is the Dec 79 issue of APL Quote Quad that has
WSIS0. Appendix B of the Draft International Standard has WSIS1.
There are several differences:
(1) There is one more class of canonical representation vector:
WSIS0 WSIS1 Meaning
C C Character array
N N Numeric array
F F Function
P P Pseudovariable
Q Executable expression
X X Installation dependent
The "Q" class is for executable expressions. For example you could have
19Q#fx 2 2 4 FOO A+23
(The "#" stands for an APL "quad".) This class Q could replace C, N,
and F, if you wanted it to, but it has the complication of doubling
quotes in character strings. Not quite as clean, but it is implemented
correctly on some systems.
(2) The first Pseudovariable is changed:
From "9PWSIS 0 0" to "9PWSIS 0 1".
(3) There are two new Pseudovariables that allow representation of an
enormous character set. At present, still only the APL char set (regn
no. 68) can be used in a conforming program. But DATA may be chosen
from any registered character set. (There are many.)
(a) BITS
this tells how many bits are being used
for each character (at least 8).
(b) ESCAPE
this identifies what character set each
element of the atomic vector is taken from.
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I hope that helps. There are more details, of course, but that is a
rough outline. You can find out more by looking at APL Quote Quad,
Volume 14, Number 2, December 1983. This was the issue that was
dedicated to the APL Standard. In it there is something called Annex
B, which is devoted to WSIS1. There have been some corrections to the
standard since then, but the outline of the standard today is pretty
much as it was then. I think that Annex B has not changed, except that
it has been re-typeset, and possibly typos may have crept in. But, to
get the best copy, you should get in touch with the International
Standards Organization, and ask for Draft Proposal 8485, February 25,
1986. As an easier alternative, contact your local national standards
committee for the latest version. These are the countries that I know
of that have active working groups.
Country Standards Group
USA ANSI X3J10
UK BSI APL Working Group
Canada CSA APL WG
France AFNOR APL Group de Travail
W.Germany DIN
Sweden SIS
Belgium ?