When I develop the project in Swift, The Swift.print is the most commonly used.
But some times I wish more readable dectect value like use dump, even if I programming in Combine.
So I create the combine extension for dump.
publisher
.dump()
.sink { ... }
.store(&bag)
| import Foundation | |
| import Combine | |
| extension Publishers { | |
| private class BagContainer { | |
| var bag = Set<AnyCancellable>() | |
| } | |
| public struct Dump<Upstream> : Publisher where Upstream : Publisher { | |
| private var bagContainer = BagContainer() | |
| public typealias Output = Upstream.Output | |
| public typealias Failure = Upstream.Failure | |
| public let upstream: AnyPublisher<Output, Failure> | |
| public let prefix: String | |
| public init<P: Publisher>(_ publisher: P, _ prefix: String = "") where P.Output == Output, P.Failure == Failure { | |
| self.prefix = prefix | |
| self.upstream = publisher.eraseToAnyPublisher() | |
| } | |
| public func receive<S: Combine.Subscriber>(subscriber: S) where S.Input == Output, S.Failure == Failure { | |
| binding(upstream, prefix) | |
| upstream.subscribe(subscriber) | |
| } | |
| private func binding<P: Publisher>(_ publisher: P, _ prefix: String) { | |
| let prefix = prefix.isEmpty ? "" : "\(prefix) " | |
| publisher.sink(receiveCompletion: { | |
| switch $0 { | |
| case .finished: | |
| Swift.print("\(prefix)Finished -----------------") | |
| case .failure(let error): | |
| Swift.print("\(prefix)Error in -----------------") | |
| Swift.dump(error) | |
| Swift.print("\(prefix)Error End -----------------") | |
| } | |
| }, receiveValue: { value in | |
| Swift.print("\(prefix)Value in -----------------") | |
| Swift.dump(value) | |
| Swift.print("\(prefix)Value End -----------------") | |
| }).store(in: &bagContainer.bag) | |
| } | |
| } | |
| } | |
| extension Publisher { | |
| public func dump(_ prefix: String = "") -> Publishers.Dump<Self> { | |
| return Publishers.Dump(self, prefix) | |
| } | |
| public func debugDump(_ prefix: String = "")-> AnyPublisher<Self.Output, Self.Failure> { | |
| #if DEBUG | |
| return dump(prefix).eraseToAnyPublisher() | |
| #else | |
| return AnyPublisher(self) | |
| #endif | |
| } | |
| } |