enum inheritance

[Dicebot]

On Monday, 15 July 2013 at 18:26:26 UTC, JS wrote:
> Original I had it as a class. I'm not sure if it matters much 
> between a class and a struct though?

It does matter a lot. structs are value types, classes are 
polymorphic reference types. There is a nice summary table in 
docs: http://dlang.org/struct.html , please notice that 
"inheritance" and this "final" applies only for classes.

> In any case, I solved this problem by using an attribute to 
> test instead of using isMutable. Obviously this requires adding 
> a symbol but not a huge deal.
>
> e.g.,
>
> @Enum immutable struct ...
>
> and hasAttribute(T, Enum) replaces isMutable(T).

Yeah, that may work, despite being not that pretty. I personally 
think it is better for now chose some not-that-elegant approach 
in your code, at least until enums will become more robust. 
Currently it tries to workaround some very basic type system 
assumptions, which rarely ends good.