Trait for "can be instantiated"?

[Ben Jones]

On Tuesday, 10 May 2022 at 16:05:15 UTC, H. S. Teoh wrote:
> Using wrapper structs, etc., for this is IMO total overkill. 
> Just use an enum for your token types.  Something like this 
> would suffice:

That's basically what sumtype is going to do for me, but 
(hopefully) more safely. Also, the token types are "user 
defined,"  my lexer just grabs everything annotated with @Token 
and passes those types/wrapped enums to sumtype.