Hi there,
I’m interested if this idea has some potential future in Swift or not.
Currently RawRepresentable enums accept only a subset of literal types like
String, Character and the Integer family (enum Name : String { … }).
Sometimes this is not enough for my use-case and I wish I could feed my enums
with other Hashable types!
As a workaround I can create a custom struct or even a class and conform it to
RawRepresentable and fake an enum with some static variables (similar to what
is done with OptionSet types).
The problem there is that I cannot use the same switch pattern matching like
with enums. I’d wish either enums could accept Hashable types (maybe with some
restriction) or the existence on a protocol to build custom enum-like types
with strucs/classes and use the same switch pattern matching.
struct A : Hashable { /* implement everything */ }
// Variant 1:
enum Test : A {
case something = A(rawValue: A(value: "something"))
case nothing = A(rawValue: A(value: "nothing"))
}
// Variant 2:
protocol SomeFancyName : RawRepresentable { … }
struct Test : SomeFancyName {
let rawValue: A
init?(rawValue: A) {
// Implement + reject unwanted `A`s
}
static let something = A(rawValue: A(value: "something"))
static let nothing = A(rawValue: A(value: "nothing"))
}
let value = Test.something
switch value {
case .something:
// handle
case .nothing:
// handle
// Because of `SomeFancyName` the switch can use enum-like pattern matching +
does not need the `default` case when all cases are present
}
--
Adrian Zubarev
Sent with Airmail
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