[NTG-context] \unit parser ignoring case, in some cases.

[Gavin]

Hi Alan, Hans, and List,

> On Mar 13, 2023, at 8:10 PM, Alan Braslau via ntg-context <ntg-context at ntg.nl> wrote:
> On Mon, 13 Mar 2023 15:55:50 -0600 Gavin via ntg-context <ntg-context at ntg.nl> wrote:
>>> you can look at phys-dim and see plenty of short and long keys and
>>> making all case insensitive is asking for troubles  
>> 
>> Indeed, I would like to make NONE of them case insensitive. But
>> currently, when I register an upper case key (C=coulomb) it messes up
>> the lower case prefix (“cm" gets typeset as C•m). I was expecting the
>> parser to distinguish between the “C” and “c”, but it doesn’t. Is
>> that intended?
> 
> Indeed, \unit{} should allow (and presently does not) K, C, etc.

I agree. I added the following lines to phys-dim.lua, following line 461

    C  = "coulomb",
    K  = "kelvin",
    N  = "newton",

This provided the desired capital shortcuts without compromising the lowercase prefixes. Hans, could we get those added to phys-dim.lua in the distribution? I would be happy to do a more comprehensive search for shortcuts to add, but those are the three I and my collaborators are using now.

Looking at why my \registerunit attempt failed, I found that when you register a unit, both your capitalization, and an all lowercase version are registered. Here is an example, where I register “ReTeM” but \unit{1 retem} also works.

\starttext

\registerunit[unit][ReTeM=myunit]
\setupunittext[myunit=reTeM]

\startformula
  \unit{1 ReTeM} = \unit{1 retem} \neq \unit{1 reteM}
\stopformula

\stoptext

The results are case sensitive, so \unit{1 reteM} does not work. The lowercase version is produced for all “long” units, but not for shortcuts. (See phys-dim.lua, lines 766-771 where the Lua string function “lower” is used.) Perhaps we could use a \registershortcut command that does not get the “lower" treatment. I will look into it some more.

Thanks!
Gavin


P.S. I think there is a spelling error in phys-dim.lua, lines 974-981.

local mapping = {
    prefix   = "prefixes",
    unit     = "units",
    operator = "operators",
    suffixe  = "suffixes",
    symbol   = "symbols",
    packaged = "packaged",
}

The key “suffixe” should probably be “suffix”.