Sorry for pushing this back, but I really would like to read any feedback for
this idea of mine. ;)
--
Adrian Zubarev
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Am 4. Mai 2016 bei 22:38:33, Adrian Zubarev (adrian.zuba...@devandartist.com)
schrieb:
This one have bothered me for days, since the idea came to my mind.
I don't want to be too futuristic so here are my first thoughts.
What if Swift 3 would have the ability to merge types and protocols together?
Sure we will see generic typealias in Swift 3 but it doesn't allow us merge
value types which conforms to specific protocols (if there is a need).
protocol SomeProtocol {
func boo()
}
// this use-case can be solved with generic typealias in Swift 3 (at least for
classes), but it is not the only one usecase of type merging
func foo(mergedInstance: type<UIView, SomeProtocol>) {
mergedInstance.removeFromSuperview() // just for the example
mergedInstance.boo()
}
extension UIButton: SomeProtocol { /* implemnt boo() */ }
let button: SomeProtocol = UIButton() // decouple UIButton first
Ok now I want to use one instance as SomeProtocol and UIView.
// another possible use-case
if let mergedView = button as? type<UIView, SomeProtocol> {
mergedView.removeFromSuperview() // just for the example
mergedView.boo()
}
More detailed design:
- type<> can contain only one value or reference type and n protocols
- value or reference type should always be the first type
- type<> should always contain at least 2 types (one value or reference type
and min. one protocol)
- reference types does represent one possible super/base type of the actuall
type
* class A {}
* class B: A {}
* class C: B {}
* possible types for B and C: type<B, AnyProtocolType, ...> or type<A,
AnyProtocolType, ...>
- the dynamicType/Self instance passed to type<> conforms to all protocols
type<> contains
If there is more rules one would apply to this idea feel free to discuss them
here.
--
Adrian Zubarev
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