enum

[Dominikus Dittes Scherkl]

On Friday, 11 April 2014 at 10:07:13 UTC, Walter Bright wrote:
> The point being that D is powerful enough that you can use 
> structs and templates to create all kinds of types with custom 
> behaviors. They don't all need to be baked into the core 
> language.

Yes, but it supports enum as a separate kind of types - but there 
are two fundamental different usages of enums, for which a totaly 
different set of operations is required:
1: "real" enums, that enumerate all possible values, that can be 
used in final switch and that shouldn't allow for any kind of 
arithmetic performed on them - not even increment (maybe a enum 
count, but thats all)
2: types with some named constants, that should NOT be usable in 
final switch but provide arithmetic, discontinual values and 
everything what enum at the moment falsely provides.

So, D need not provide enums (both kinds can be build from 
structs) but if it does, it should not unify them in ONE type. 
There are too different expectations to enums as that one type 
can satisfy them all. --> add a new type ("partial_enum" or 
whatever) that can be used with arithmetics like flag-arrays or 
COLOR, _and_ forbid the arithmetics for real enums.