diff --git a/Rx.playground/Pages/Connectable_Operators.xcplaygroundpage/Contents.swift b/Rx.playground/Pages/Connectable_Operators.xcplaygroundpage/Contents.swift
index d7637db0..28587da8 100644
--- a/Rx.playground/Pages/Connectable_Operators.xcplaygroundpage/Contents.swift
+++ b/Rx.playground/Pages/Connectable_Operators.xcplaygroundpage/Contents.swift
@@ -49,7 +49,7 @@ func sampleWithPublish() {
     _ = intSequence
         .subscribeNext { print("Subscription 1:, Event: \($0)") }
     
-    delay(2) { intSequence.connect() }
+    delay(2) { _ = intSequence.connect() }
     
     delay(4) {
         _ = intSequence
@@ -81,7 +81,7 @@ func sampleWithReplayBuffer() {
     _ = intSequence
         .subscribeNext { print("Subscription 1:, Event: \($0)") }
     
-    delay(2) { intSequence.connect() }
+    delay(2) { _ = intSequence.connect() }
     
     delay(4) {
         _ = intSequence
@@ -115,7 +115,7 @@ func sampleWithMulticast() {
     _ = intSequence
         .subscribeNext { print("\tSubscription 1:, Event: \($0)") }
     
-    delay(2) { intSequence.connect() }
+    delay(2) { _ = intSequence.connect() }
     
     delay(4) {
         _ = intSequence
diff --git a/Rx.playground/Pages/Creating_and_Subscribing_to_Observables.xcplaygroundpage/Contents.swift b/Rx.playground/Pages/Creating_and_Subscribing_to_Observables.xcplaygroundpage/Contents.swift
index 7f751cf0..0df97e9b 100644
--- a/Rx.playground/Pages/Creating_and_Subscribing_to_Observables.xcplaygroundpage/Contents.swift
+++ b/Rx.playground/Pages/Creating_and_Subscribing_to_Observables.xcplaygroundpage/Contents.swift
@@ -190,7 +190,7 @@ example("deferred") {
 example("error") {
     let disposeBag = DisposeBag()
         
-    Observable<Int>.error(Error.test)
+    Observable<Int>.error(TestError.test)
         .subscribe { print($0) }
         .addDisposableTo(disposeBag)
 }
diff --git a/Rx.playground/Pages/Debugging_Operators.xcplaygroundpage/Contents.swift b/Rx.playground/Pages/Debugging_Operators.xcplaygroundpage/Contents.swift
index fdde6b68..4165dad9 100644
--- a/Rx.playground/Pages/Debugging_Operators.xcplaygroundpage/Contents.swift
+++ b/Rx.playground/Pages/Debugging_Operators.xcplaygroundpage/Contents.swift
@@ -24,7 +24,7 @@ example("debug") {
         observer.onNext("🍊")
         
         if count < 5 {
-            observer.onError(Error.Test)
+            observer.onError(TestError.test)
             print("Error encountered")
             count += 1
         }
diff --git a/Rx.playground/Pages/Error_Handling_Operators.xcplaygroundpage/Contents.swift b/Rx.playground/Pages/Error_Handling_Operators.xcplaygroundpage/Contents.swift
index 0383aa15..37c6b6d4 100644
--- a/Rx.playground/Pages/Error_Handling_Operators.xcplaygroundpage/Contents.swift
+++ b/Rx.playground/Pages/Error_Handling_Operators.xcplaygroundpage/Contents.swift
@@ -29,7 +29,7 @@ example("catchErrorJustReturn") {
     sequenceThatFails.onNext("😨")
     sequenceThatFails.onNext("😡")
     sequenceThatFails.onNext("🔴")
-    sequenceThatFails.onError(Error.Test)
+    sequenceThatFails.onError(TestError.test)
 }
 /*:
  ----
@@ -55,7 +55,7 @@ example("catchError") {
     sequenceThatFails.onNext("😨")
     sequenceThatFails.onNext("😡")
     sequenceThatFails.onNext("🔴")
-    sequenceThatFails.onError(Error.Test)
+    sequenceThatFails.onError(TestError.test)
     
     recoverySequence.onNext("😊")
 }
@@ -75,7 +75,7 @@ example("retry") {
         observer.onNext("🍊")
         
         if count == 1 {
-            observer.onError(Error.Test)
+            observer.onError(TestError.test)
             print("Error encountered")
             count += 1
         }
@@ -109,7 +109,7 @@ example("retry maxAttemptCount") {
         observer.onNext("🍊")
         
         if count < 5 {
-            observer.onError(Error.Test)
+            observer.onError(TestError.test)
             print("Error encountered")
             count += 1
         }
diff --git a/Rx.playground/Pages/Working_with_Subjects.xcplaygroundpage/Contents.swift b/Rx.playground/Pages/Working_with_Subjects.xcplaygroundpage/Contents.swift
index 7d8e4da2..b61ffd75 100644
--- a/Rx.playground/Pages/Working_with_Subjects.xcplaygroundpage/Contents.swift
+++ b/Rx.playground/Pages/Working_with_Subjects.xcplaygroundpage/Contents.swift
@@ -18,7 +18,7 @@ extension ObservableType {
      Add observer with `id` and print each emitted event.
      - parameter id: an identifier for the subscription.
      */
-    func addObserver(id: String) -> Disposable {
+    func addObserver(_ id: String) -> Disposable {
         return subscribe { print("Subscription:", id, "Event:", $0) }
     }
     
diff --git a/Rx.playground/Sources/SupportCode.swift b/Rx.playground/Sources/SupportCode.swift
index 298f20e7..e830a8f7 100644
--- a/Rx.playground/Sources/SupportCode.swift
+++ b/Rx.playground/Sources/SupportCode.swift
@@ -5,16 +5,16 @@ import Foundation
  - parameter description: example description
  - parameter action: `Void` closure
  */
-public func example(description: String, action: @noescape(Void) -> Void) {
-    printExampleHeader(description: description)
+public func example(_ description: String, action: @noescape(Void) -> Void) {
+    printExampleHeader(description)
     action()
 }
 
-public func printExampleHeader(description: String) {
+public func printExampleHeader(_ description: String) {
     print("\n--- \(description) example ---")
 }
 
-public enum Error: Swift.Error {
+public enum TestError: Swift.Error {
     case test
 }
 
@@ -24,7 +24,7 @@ public enum Error: Swift.Error {
  - parameter delay: time in seconds to wait before executing `closure`
  - parameter closure: `Void` closure
  */
-public func delay(delay: Double, closure: (Void) -> Void) {
+public func delay(_ delay: Double, closure: (Void) -> Void) {
 
     let delayTime = DispatchTime.now() + DispatchTimeInterval.seconds(Int(delay))
     DispatchQueue.main.asyncAfter(deadline: delayTime) {