Compiler warnings (#819)

Co-authored-by: Stefan Fessler <[email protected]>

Author: apps4everyone

Sources/Disposable.swift

@@ -8,7 +8,7 @@
 
 /// Represents something that can be “disposed”, usually associated with freeing
 /// resources or canceling work.
-public protocol Disposable: class {
+public protocol Disposable: AnyObject {
 	/// Whether this disposable has been disposed already.
 	var isDisposed: Bool { get }
 

Sources/Property.swift

@@ -12,7 +12,7 @@ import Glibc
 ///
 /// Only classes can conform to this protocol, because having a signal
 /// for changes over time implies the origin must have a unique identity.
-public protocol PropertyProtocol: class, BindingSource {
+public protocol PropertyProtocol: AnyObject, BindingSource {
 	/// The current value of the property.
 	var value: Value { get }
 

Sources/Scheduler.swift

@@ -14,7 +14,7 @@ import Foundation
 #endif
 
 /// Represents a serial queue of work items.
-public protocol Scheduler: class {
+public protocol Scheduler: AnyObject {
 	/// Enqueues an action on the scheduler.
 	///
 	/// When the work is executed depends on the scheduler in use.

Sources/Signal.swift

@@ -415,7 +415,7 @@ extension Signal {
 	}
 }
 
-public protocol SignalProtocol: class {
+public protocol SignalProtocol: AnyObject {
 	/// The type of values being sent by `self`.
 	associatedtype Value
 
@@ -1662,7 +1662,7 @@ private enum ThrottleWhileState<Value> {
 	}
 }
 
-private protocol SignalAggregateStrategy: class {
+private protocol SignalAggregateStrategy: AnyObject {
 	/// Update the latest value of the signal at `position` to be `value`.
 	///
 	/// - parameters: