On 8/25/2015 12:07 PM, Richard Wordingham wrote:
On Tue, 25 Aug 2015 09:54:29 +0100 (BST)
William_J_G Overington <wjgo_10...@btinternet.com> wrote:
Richard Wordingham wrote:
On Mon, 24 Aug 2015 11:00:32 +0100 (BST)
William_J_G Overington <wjgo_10...@btinternet.com> wrote:
Looking at the document
http://www.unicode.org/L2/L1999/99159.pdf
that has been mentioned, the four bracket characters are therein
described as follows.
4X1F O LEFT BRACKET, REVERSE SOLIDUS TOP CORNER
4X20 C RIGHT BRACKET, REVERSE SOLIDUS BOTTOM CORNER
4X21 O LEFT BRACKET, SOLIDUS BOTTOM CORNER
4X22 C RIGHT BRACKET, SOLIDUS TOP CORNER
So it looks like the pairings in Unicode today are as originally
intended.
How so?
I was simply observing that the original pairings had the
first-listed pair of brackets listed using REVERSE SOLIDUS and had
the second-listed pair of brackets listed using SOLIDUS contrasting
that clear pairing of the brackets with the use, in the encoding into
Unicode, of TICK in the listing for each of the four of the bracket
characters that are being discussed in this thread.
You said the 'pairings in Unicode'. With the exception of decimal
digits, the scalar values of assigned characters have no *formal*
relationship to their interpretation. The scalar values are about as
significant as the difference between canonically equivalent
non-Greek, non-Korean sequences. At best the different sequences give a
hint of what the author thinks about the character. For example U+00E9
LATIN SMALL LETTER E WITH ACUTE suggests it may be though of as a
character, while <U+0065, U+0301> suggests that it may be two
characters - the diacritic could be a length mark or a tone. The
distinction is not to be relied upon - normalisation would obliterate
it.
I think William makes a reasonable point that conceiving of the "ticks"
as angled lines
and then naming their direction in pairs potentially reinforces the
notion that the sets
with matching naming were intended as pairs.
While this is being bandied about here on the list, an offline effort is
underway to
see whether it's possible to find out more about the origin and
potential use of
these marks - prior to their encoding in Unicode. We know they came from
some
SGML entity sets, but how and why they got into those is still a bit of
a mystery;
locked away in the heads of the original creator of these sets.
We may never get a more definite answer, unless someone here is conversant
with whatever field of mathematics uses these brackets, or knows someone who
is.
A./
