Use weak self reference in .sink instead of force casting

MMMAsyncLoadable.podspec

@@ -6,7 +6,7 @@
 Pod::Spec.new do |s|
 
 	s.name = "MMMAsyncLoadable"
-	s.version = "0.3.0"
+	s.version = "0.3.1"
 	s.summary = "Use async/await with MMMLoadable"
 	s.description =  s.summary
 	s.homepage = "https://github.com/mediamonks/#{s.name}"
@@ -26,4 +26,5 @@ Pod::Spec.new do |s|
 	}
 	s.source_files = [ "Sources/#{s.name}/*.swift" ]
 	s.dependency "MMMLoadable"
+    s.dependency "MMMCommonCore"
 end

Package.swift

@@ -18,12 +18,13 @@ let package = Package(
 		)
     ],
     dependencies: [
-        .package(name: "MMMLoadable", url: "https://github.com/mediamonks/MMMLoadable", .upToNextMajor(from: "1.7.0"))
+        .package(name: "MMMLoadable", url: "https://github.com/mediamonks/MMMLoadable", .upToNextMajor(from: "1.7.0")),
+        .package(name: "MMMCommonCore", url: "https://github.com/mediamonks/MMMCommonCore", .upToNextMajor(from: "1.8.2"))
     ],
     targets: [
         .target(
 			name: "MMMAsyncLoadable",
-			dependencies: ["MMMLoadable"]
+			dependencies: ["MMMLoadable", "MMMCommonCore"]
 		),
         .testTarget(
             name: "MMMAsyncLoadableTests",

Sources/MMMAsyncLoadable/AsyncLoadableObserver.swift

@@ -5,6 +5,7 @@
 
 import Foundation
 import MMMLoadable
+import MMMCommonCore
 
 /// ``MMMLoadableObserver`` that supports asynchronous closures as it's callback.
 public final class AsyncLoadableObserver: MMMLoadableObserver {
@@ -31,8 +32,12 @@ extension MMMPureLoadableProtocol {
     /// - Returns: The observer, you usually want to store this outside of the scope, e.g.
     ///            in a private property so it doesn't deallocate right away.
     public func sink(_ block: @Sendable @escaping (Self) async -> Void) -> AsyncLoadableObserver? {
-        return AsyncLoadableObserver(loadable: self) { loadable in
-            await block(loadable as! Self)
+        return AsyncLoadableObserver(loadable: self) { [weak self] loadable in
+            guard let self = self else {
+                assertionFailure("\(MMMTypeName(Self.self)) was lost inside the observer callback?")
+                return
+            }
+            await block(self)
         }
     }
 }