[NTG-context] Math literal colon

[Hans Aberg]

> On 24 Jul 2015, at 16:26, Hans Hagen <pragma at wxs.nl> wrote:
> 
> On 7/24/2015 4:08 PM, Hans Aberg wrote:
> 
>> I was thinking of just having the two, \colon and \ratio. Looking into some books before electronic typesetting, the spacing of the latter can vary widely: some do not use spaces at all. So a set might look
>>   {x:x < a}
>> instead of
>>   {x : x < a}
>> But that would be a typographical issue, rather than semantic.
> 
> but we do need to deal with the typographic issue

Yes, that is what I meant, typographic adjustments on top.

> and unicode is not covering every symantic (otherwise we would have more)

It covers all standard symbols at the end of 1990s. Since then a number of symbols have come into use. There was a discussion about that on the Unicode list. Those using them might add them as well. But new characters are created, so there is a need for accessing them as well.