On Monday, 15 April 2019 at 10:34:42 UTC, Anton Fediushin wrote:
On Monday, 15 April 2019 at 10:06:30 UTC, XavierAP wrote:
You have defined your sub-typing the opposite way that you
wanted it to work: every `Enum` is an `internal`, but the
other way around an `internal` may not work as an `Enum`. Your
`fun` would in principle work if it were defined with an
`internal` but passed an `Enum`... Of course you have defined
`internal` as nested private so no... But then how did you
want anything to work if no one outside Enum knows the
super-type?
Isn't this how subtyping works for integers and other types?
For example, you have subtyped an integer and added some new
methods to it?
Yes (leaving aside whether stuff is private or nested) but you
are using the types' relationship the other way around. You have:
static assert(is(Enum : internal));
But you are defining and calling fun() as if it were the other
way around (internal : Enum)
