And
in this particular case, the usage of floor and ceiling symbols
in math does not prevent recognizing that their usage *even in
math* as bracketing pairs on symbols is delimiter- and punctuation-like
in practice.
One may note the common use of the greater-than and less-than signs as angle brackets in many publications including the Unicode standard. I don't think that necessitates coding separate characters.
Remember, folks, that Unicode is a *plain text* standard. Unless
medievalists have some pretty compelling reason for *distinguishing*
in their documents mathematical floor/ceiling notation from
their textual conventions of corner bracketing, there really
is nothing standing in the way of using the characters as
recommended in the standard, except for an aversion to the specific
design of the glyphs in the most widely available Unicode generic
fonts.
But the half square brackets to me fall into a different category.
I am familiar with then from numerous published texts. They are indeed widely used to indicate editorial insertion guesses for missing or undecipherable material and I have never seen them look like anything but the top *halves* of normal square brackets.
The ceiling characters as shown in the standard and in Kent Karlson's paper don't fit in appearance. Of course medievalists and editors of ancient middle-eastern texts will "have an aversion to the specific design of the glyphs" since the design is wrong for half square brackets.
If I were editing texts using that convention and wished to stick to Unicode I'd probably superscript U+23A1 LEFT SQUARE BRACKET UPPER CORNER and U+23A4 RIGHT SQUARE BRACKET UPPER CORNER as the closest approximation, kludge though that would be.
Left ceiling and right ceiling might do in plain text as a reasonable reminder of the characters that should be used. Or 231C TOP LEFT CORNER and 231B TOP RIGHT CORNER. But it would be like using the digit 3 for yogh or ezh or Egyptian glottal stop. It works well enough to get the meaning across, but it isn't the right character.
I'm not at all sure what "general-purpose corner brackets" are.
Jim Allan
