Merge commit '7621e2f8dec938cf48181c8b10afc9b01f444e68' into beta

submodules/SSignalKit/SwiftSignalKit/Source/ValuePipe.swift

@@ -0,0 +1,39 @@
+import Foundation
+
+public final class ValuePipe<T> {
+    private let subscribers = Atomic(value: Bag<(T) -> Void>())
+    
+    public init() {
+    }
+    
+    public func signal() -> Signal<T, NoError> {
+        return Signal { [weak self] subscriber in
+            if let strongSelf = self {
+                let index = strongSelf.subscribers.with { value -> Bag<T>.Index in
+                    return value.add { next in
+                        subscriber.putNext(next)
+                    }
+                }
+                
+                return ActionDisposable { [weak strongSelf] in
+                    if let strongSelf = strongSelf {
+                        strongSelf.subscribers.with { value -> Void in
+                            value.remove(index)
+                        }
+                    }
+                }
+            } else {
+                return EmptyDisposable
+            }
+        }
+    }
+    
+    public func putNext(_ next: T) {
+        let items = self.subscribers.with { value -> [(T) -> Void] in
+            return value.copyItems()
+        }
+        for f in items {
+            f(next)
+        }
+    }
+}