Allows the use of part of the language keywords?

[Cauterite via Digitalmars-d]

On Sunday, 28 August 2016 at 04:32:46 UTC, Basile B. wrote:
> You must keep track of the previous token, which is not usually 
> done in a scanner.

That sounds like a pretty trivial feature to me. There's no way 
that's a legitimate obstacle.