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STRUCT

Sink

public struct Sink<Value>

Sink is a type that receives incoming values (commonly events or WorkflowAction)

Use RenderContext.makeSink to create instances.

Methods

init(_:)

public init(_ onValue: @escaping (Value) -> Void)

Initializes a new sink with the given closure.

send(_:)

public func send(_ value: Value)

Sends a new event into the sink.

  • Parameter event: The value to send into the sink.

Parameters

Name Description
event The value to send into the sink.

contraMap(_:)

public func contraMap<NewValue>(_ transform: @escaping (NewValue) -> Value) -> Sink<NewValue>

Generates a new sink of type NewValue.

Given a transform closure, the following code is functionally equivalent:

sink.send(transform(value))

sink.contraMap(transform).send(value)

Trivia: Why is this called contraMap? - map turns Type<T> into Type<U> via (T)->U. - contraMap turns Type<T> into Type<U> via (U)->T

Another way to think about this is: map transforms a type by changing the output types of its API, while contraMap transforms a type by changing the input types of its API.

  • Parameter transform: An escaping closure that transforms T into Event.

Parameters

Name Description
transform An escaping closure that transforms T into Event.