Swift找不到协议保证的方法

Question

我正在努力想出一种方法来减少使用Cleanse向ViewController进行依赖注入的样板代码。但是，绝对卡在Cleanse.Component样板的类型擦除类中。我做错了什么？

（包括Code和XCode快照，方便您阅读）

import Foundation
import Cleanse

protocol CleanseInjectable {
    func inject(args: Any...) -> Void
    func prepare() -> Void
}

extension CleanseInjectable {
    func inject(args: Any...) -> Void {

    }
}

class AnyCleansePropertyInjectionComponent<TargetType: AnyObject, CleanseInjectable>: Cleanse.Component {
    typealias Root = PropertyInjector<TargetType>

    func configure<B : Binder>(binder binder: B) {
        binder
            .bindPropertyInjectionOf(TargetType.self)
            .to(injector: (TargetType.self as! CleanseInjectable.Type).inject)
    }
}

我得到的错误与任何Swift协议错误一样奇怪，事后才明白这一点：Type 'CleanseInjectable' has no member 'inject'？！

Answer 1

此版本似乎可以解决错误！似乎Swift无法理解TargetType: AnyObject, CleanseInjectable是否与protocol CleanseInjectable: class相当于约束。

import Cleanse

protocol CleanseInjectable: class {
    func inject(args: Any...) -> Void
    func prepare() -> Void
}

extension CleanseInjectable {
    func inject(args: Any...) -> Void {

    }
}

class AnyCleansePropertyInjectionComponent<TargetType: CleanseInjectable>: Cleanse.Component {
    typealias Root = PropertyInjector<TargetType>

    func configure<B : Binder>(binder binder: B) {
        binder
            .bindPropertyInjectionOf(TargetType.self)
            .to(injector: TargetType.inject)
    }
}

编辑：我已完成的清洁锅炉板清除器（在运行时未经测试，最早将更新），以获得乐趣和灵感！

import Cleanse

protocol CleanseInjectable: class {
    var cleanseComponent: AnyCleansePropertyInjectionComponent<Self>? { get }
    func inject(args: Any...) -> Void
    func prepare() -> Void
}

extension CleanseInjectable {
    func inject(args: Any...) -> Void {
        // Override me to do something useful, brah!
    }

    func prepare() -> Void {
        if (cleanseComponent != nil) {
            (try! cleanseComponent!.build()).injectProperties(into: self)
        }
    }
}

class AnyCleansePropertyInjectionComponent<TargetType: CleanseInjectable>: Cleanse.Component {
    typealias Root = PropertyInjector<TargetType>

    func configure<B : Binder>(binder binder: B) {
        binder
            .bindPropertyInjectionOf(TargetType.self)
            .to(injector: TargetType.inject)
    }
}