What is the current Unicode stance on subscripts and superscripts for mathematical use?

John Hudson john at tiro.ca
Mon Jun 22 16:10:32 CDT 2020

On 22062020 11:34 am, Doug Ewell wrote:
> So, does that mean you don't think L2/18-206 will fly?

Has it shown any signs of flying in the past two years? or am I being 
trolled? :)

I'll bite:

That document is targeting issues in general typographic display 
variants and muddies the character/glyph distinction. Most of what it 
calls for are clear cases of typographic glyph processing, e.g. 
smallcaps as variants of uppercase characters. In that respect, it at 
once goes too far in calling for smallcap encoding for a large number of 
existing uppercase characters and not nearly far enough in ignoring vast 
numbers of existing characters outside the small European subset 
identified in the document.

The author seems also not to understand that existing 'small capitals' 
in Unicode are not typographic smallcap variants but distinct letters in 
some phonetic notation systems.

The author is not wrong to point out that the existence of some super- 
and subscript characters in Unicode doesn't always play well with font 
and algorithmic display of additional characters with super- and 
subscript styling: size, weight, and alignments can vary, depending on 
the path from the encoded characters to the styled display, how well the 
font has been made, and what algorithms are used. But these problems are 
not solved by encoding a bunch of additional super- and subscript 
characters. The problems may be pushed further out — at least for 
European users of the Latin script — but not solved.

Mathematical notation is a different case: a specialised writing system 
in which style, size, and relative position all have semantic meaning. 
It needs a different model for both encoding and layout than typical 
language text and typography.



John Hudson
Tiro Typeworks Ltd    www.tiro.com
Salish Sea, BC        tiro at tiro.com

NOTE: In the interests of productivity, I am currently
dealing with email on only two days per week, usually
Monday and Thursday unless this schedule is disrupted
by travel. If you need to contact me urgently, please
use some other method of communication. Thank you.

More information about the Unicode mailing list