Implementing typestate

[Freddy via Digitalmars-d]

On Tuesday, 15 September 2015 at 18:10:06 UTC, BBasile wrote:
> Ok, sorry I didn't know this concept so far.
> So there would be a kind of 'compile-time instance' of File 
> with a modifiable member ?

A simplified version of this: 
https://en.wikipedia.org/wiki/Typestate_analysis
Where types can have compile time state(enum) that change as they 
are used.