Adds optional parameter to `timer` operator.

RxSwift/Observables/Observable+Time.swift

@@ -103,7 +103,7 @@ extension Observable where Element: SignedIntegerType {
     - returns: An observable sequence that produces a value after due time has elapsed and then each period.
     */
     @warn_unused_result(message="http://git.io/rxs.uo")
-    public static func timer(dueTime: RxTimeInterval, period: RxTimeInterval, scheduler: SchedulerType)
+    public static func timer(dueTime: RxTimeInterval, period: RxTimeInterval? = nil, scheduler: SchedulerType)
         -> Observable<E> {
         return Timer(
             dueTime: dueTime,
@@ -113,27 +113,6 @@ extension Observable where Element: SignedIntegerType {
     }
 }
 
-extension Observable where Element: SignedIntegerType {
-    /**
-    Returns an observable sequence that produces a single value at the specified absolute due time, using the specified scheduler to run the timer.
-
-    - seealso: [timer operator on reactivex.io](http://reactivex.io/documentation/operators/timer.html)
-
-    - parameter dueTime: Time interval after which to produce the value.
-    - parameter scheduler: Scheduler to run the timer on.
-    - returns: An observable sequence that produces a value at due time.
-    */
-    @warn_unused_result(message="http://git.io/rxs.uo")
-    public static func timer(dueTime: RxTimeInterval, scheduler: SchedulerType)
-        -> Observable<E> {
-        return Timer(
-            dueTime: dueTime,
-            period: nil,
-            scheduler: scheduler
-        )
-    }
-}
-
 // MARK: take
 
 extension ObservableType {

Tests/RxSwiftTests/Tests/Observable+SingleTest.swift

@@ -1307,12 +1307,12 @@ extension ObservableSingleTest {
                 errors.scan((0, nil)) { (a: (Int, NSError!), e) in
                     (a.0 + 1, e)
                 }
-                .flatMap { (a, e) -> Observable<Int> in
+                .flatMap { (a, e) -> Observable<Int64> in
                     if a >= 4 {
                         return Observable.error(e)
                     }
 
-                    return Observable<Int>.timer(RxTimeInterval(a * 50), scheduler: scheduler)
+                    return Observable<Int64>.timer(RxTimeInterval(a * 50), scheduler: scheduler)
                 }
             }
         }