unicode combinig mark/ std.uni question

[Dmitry Olshansky]

On Tuesday, 5 December 2017 at 20:04:29 UTC, ikod wrote:
> Hello,
>
> I have to create very basic IDNA (Internationalized Domain 
> Names in Applications) library. There are two parts in IDNA - 
> user input checks and punycode encoding/decoding.
>
> Punycode part already completed, and now I have to add some 
> checks but I'm weak in unicode and cant find proper way to 
> express these tests using std.uni.
>
> Here are list of prohibited domain labels 
> (https://tools.ietf.org/html/rfc5891):

Well std.uni gives you ability to build fast lookup tables and a 
set of codepoints type, I don’t think we have any of the sets you 
listed prepared in std. Maybe combining marks are, check the docs.