XPL (For Annie Fisher)

[holmgrn@xxxxxxxx]

For Annie Fisher:

> I welcome ... more tips like this,... xpl techniques,
> and such... I'll hate it though if the energy
> is focused on .DLG. I guess anyone who liked A La
> Carte will love .DLG but my A La Carte stayed in the
> box, where I believe menus and dialog boxes belong.
> --Annie F.

Absolutely. Couldn't phrase it better. A La Carte was the
beginning of the end, the road to perdition, the stupidification
of XyWriters and the repeal of speed and power. Tending in the
direction of Macs. Particularly scary is that schools are
embracing this philosophy too; the only "computing" they teach is
advanced button pushing. Same in medicine. Psychiatry is dead;
HMOs treat complex/unusual mental states by medicating them.
Look at the energy
XyQuest and TTG have poured into menus! It seems to me that if
we wanted hierarchical menus, we'd use Word or WP, which
(let's face it) do it much better. At the same time, one
offshoot of all this is that they've actually enhanced XPL
significantly (it was absolutely moribund -- not a single new
command that I can recall -- between II+ and Signature).
For their own convenience, of course! Exclusively due to their
own requirements flowing from the Menus; not even one whit due to
what users might have requested over the years, or might find
useful. Very few of these enhancements are documented; you have
to study DLG to figure them out -- so
DLG is profoundly instructive, albeit unintentionally.

> Would be real nice to be able to
> use the first byte of a null, e.g., in xpl routines
> that search function symbols instead of crudely BD'ing
> over the second two bytes... I hate when a loose partial
> null gets hooked to a return in text so I can't BD or CL
> over it, and when I try to use the single-byte char in
> text that's all that happens--once I get
> control of the cursor again.

Ahhhh -- you lost me. Could you expand a bit on your
understanding of nulls (Ascii-0's?) in functions? Could you give
an example of a "loose partial null" that gets "hooked to a
return"? Also, "the single-byte char in text" is which char? I
think we use different lexicons! (Which is understandable,
because these problems are so seldom discussed or described, thus
no vocabulary exists for them!
And virtually nobody understands why these phenomena occur.
In III+, Sig, and early IV, it frequently happened in blocks of
XPL that there were characters that appeared at the beginning or
end of lines -- on the line wrap, in other words -- which didn't
display properly, and which the cursor would "hop over" -- refuse
to rest upon. Is this what you're talking about? I always
attributed this to one of two causes. Either they were "hot"
characters, like function WL for example, which consists of
Ascii-255+128+255 and which wants to bond with two following
characters to the right, or possibly with hidden screen control
characters that are creating color, soft line wraps, etc
(CTRLCHAR.TXT gives a sense of these complex, deep-background
manipulations); or else there was an inadvertent combination of
characters creating bizarre functions.

Try this (in Xy4, eXPanded mode): command PFUN WL, then write
"FFe" immediately after the function WL. Now move the cursor
back and forth over these characters. Notice how, moving
_backwards_, the cursor hops from the character "e" in "FFe" to
the beginning of "WL ", a hop of five characters. Try another
experiment: put your cursor on or before func WL, and SEarch for "Fe". Not found. Now
SEarch for "FFe". Found! Now change FFe to FEe, and move the
cursor backwards: the hop disappears. These things are all
related to the behavior of Ascii-255. CHange commands also
operate abnormally when confronted with strings
(sequences of characters) like these. Such aberrations
-- plentiful, and known for ten+ years -- just simply are never
fixed, partially because seldom reported -- it's tough to report
or describe something that you don't understand -- partially
because deemed very rare, but mainly because
XyQuest/TTG doesn't discover them by themselves. After all, they
hardly use XyWrite except as a code editor; they aren't writers.
In fact, these aberrations *aren't* rare;
& they cause many irregular failures of XPL, which are rationally
unaccountable.)

If you have been XyWriting for awhile, or you used III+ at some
point, you might want to take a look at a document on TTG BBS, in
one of the file sections (probably User Programming), called
CTRLCHAR.TXT. I wrote this in 1989, so it is very much outdated.
But it mucks about in the recesses & bowels of XPL at some
length, focusing especially on the behavior of 255 and the other
"control characters". Some useful info if you're a programmer.
I could post it in \pub\eann here if the BBS is inconvenient.


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Robert J. Holmgren holmgrn@xxxxxxxx
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