May be something like this?
[https://play.nim-lang.org/#ix=20nQ](https://play.nim-lang.org/#ix=20nQ)
- Creating a type that is a non-contiguous subset of char? pmags
- Re: Creating a type that is a non-contiguous subset of ch... Araq
- Re: Creating a type that is a non-contiguous subset o... pmags
- Re: Creating a type that is a non-contiguous subs... mashingan
- Re: Creating a type that is a non-contiguous ... kaushalmodi
