SpecEnum
@Js
const mixin SpecEnum
Item metadata for an Enum spec
List the string keys
Iterate the enum items by spec and string key
Lookup enum item spec by its string key
abstract Void each(|Spec,Str| f)
Iterate the enum items by spec and string key
abstract Str[] keys()
List the string keys
abstract Spec? spec(Str key, Bool checked)
Lookup enum item spec by its string key