ReactiveSwift v2.0.0-alpha.1 Release Notes
-
๐ This is the first alpha release of ReactiveSwift 2.0. It requires Swift 3.1 (Xcode 8.3).
๐ Changes
๐ฆ Modified
Signal
lifetime semantics (#355)๐ฆ The
Signal
lifetime semantics is modified to improve interoperability with memory debugging tools. ReactiveSwift 2.0 adopted a newSignal
internal which does not exploit deliberate retain cycles that consequentially confuse memory debugging tools.๐ฆ A
Signal
is now automatically and silently disposed of, when:๐ฆ 1. the
Signal
is not retained and has no active observer; or- (New) both the
Signal
and its input observer are not retained.
It is expected that memory debugging tools would no longer report irrelevant negative leaks that were once caused by the ReactiveSwift internals.
๐ฆ
SignalProducer
resource management (#334)๐ฆ
SignalProducer
now usesLifetime
for resource management. You may observe theLifetime
for the disposal of the producedSignal
.let producer = SignalProducer<Int, NoError> { observer, lifetime in if let disposable = numbers.observe(observer) { lifetime.observeEnded(disposable.dispose) } }
๐ Two
Disposable
-accepting methodsLifetime.Type.+=
andLifetime.add
are provided to aid migration, and are subject to removal in a future release.๐ฆ Signal and SignalProducer
๐ฆ 1. All
Signal
andSignalProducer
operators now belongs to the respective concrete types. (#304)Custom operators should extend the concrete types directly.
SignalProtocol
andSignalProducerProtocol
should be used only for constraining associated types.โ 1.
combineLatest
andzip
are optimised to have a constant overhead regardless of arity, mitigating the possibility of stack overflow. (#345)flatMap(_:transform:)
is renamed toflatMap(_:_:)
. (#339)promoteErrors(_:)
is renamed topromoteError(_:)
. (#408)
๐ฆ 1.
Event
is renamed toSignal.Event
. (#376)๐ฆ 1.
Observer
is renamed toSignal.Observer
. (#376)Action
Action(input:_:)
,Action(_:)
,Action(enabledIf:_:)
andAction(state:enabledIf:_:)
are renamed toAction(state:execute:)
,Action(execute:)
,Action(enabledIf:execute:)
andAction(state:enabledIf:execute:)
respectively. (#325)
Properties
- The memory overhead of property composition has been considerably reduced. (#340)
Bindings
The
BindingSource
now requires only a producer representation ofself
. (#359)The
<~
operator overloads are now provided byBindingTargetProvider
. (#359)
Disposables
SimpleDisposable
andActionDisposable
has been folded intoAnyDisposable
. (#412)CompositeDisposable.DisposableHandle
is replaced byDisposable?
. (#363)The
+=
operator overloads forCompositeDisposable
are now hosted inside the concrete types. (#412)
Bag
๐ 1. Improved the performance of
Bag
. (#354)RemovalToken
is renamed toBag.Token
. (#354)
โฑ Schedulers
โฑ 1.
Scheduler
gains a class bound. (#333)Lifetime
Lifetime.ended
now uses the inhabitableNever
as its value type. (#392)
Atomic
Signal
andAtomic
now useos_unfair_lock
when it is available. (#342)
โ Additions
FlattenStrategy.race
is introduced. (#233, kudos to @inamiy)
race
flattens whichever inner signal that first sends an event, and ignores the rest.FlattenStrategy.concurrent
is introduced. (#298, kudos to @andersio)
concurrent
starts and flattens inner signals according to the specified concurrency limit. If an inner signal is received after the limit is reached, it would be queued and drained later as the in-flight inner signals terminate.- New operators:
reduce(into:)
andscan(into:)
. (#365, kudos to @ikesyo)
These variants pass to the closure an
inout
reference to the accumulator, which helps the performance when a large value type is used, e.g. collection.๐ฆ 1.
Property(initial:then:)
gains overloads that accept a producer or signal of the wrapped value type when the value type is anOptional
. (#396)๐ Deprecations and Removals
๐ 1. The requirement
BindingSource.observe(_:during:)
and the implementations have been removed.๐ 1. All Swift 2 (ReactiveCocoa 4) obsolete symbols have been removed.
๐ 1. All deprecated methods and protocols in ReactiveSwift 1.1.x are no longer available.
Acknowledgement
Thank you to all of @ReactiveCocoa/reactiveswift and all our contributors, but especially to @andersio, @calebd, @eimantas, @ikesyo, @inamiy, @Marcocanc, @mdiep, @NachoSoto, @sharplet and @tjnet. ReactiveSwift is only possible due to the many hours of work that these individuals have volunteered. โค๏ธ
- (New) both the