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    <p>First, you'll need a wrapper method that performs your async operation, which will return a signal. Let's assume the async operation operation takes a completion block. From the sounds of it, you don't care about the values, you want the side effects, in which case the signal does not send values, it only completes.</p> <pre><code>- (RACSignal *)asyncOperation { return [RACSignal createSignal:^RACDisposable * (id&lt;RACSubscriber&gt; subscriber) { [self asyncOperationWithCompletion:^{ [subscriber sendCompleted]; }]; return nil; // `nil` means there's no way to cancel. }]; } </code></pre> <p>EDIT: Thanks to the comment by Justin Spahr-Summers, here is a much simpler approach to chaining the operations:</p> <pre><code>RACSignal *signal = [RACSignal concat:[array.rac_sequence map:^(id entity) { return [entity asyncOperation]; }]]; </code></pre> <p>ReactiveCocoa's <code>+concat:</code> operator takes a collection of signals and subscribes to the signals one at a time, waiting for completion of one signal before subscribing to its successor. Using <code>-rac_sequence</code> here is for the purpose of mapping the entities to the operation signals.</p> <p>In this context, the use of <code>+concat:</code> achieves the same effect as the <code>-then:</code> chaining from my initial answer below.</p> <hr> <p>With the RAC wrapper, a solution is to start with an empty signal, and build a chain by iterating over the entities and assembling the operations using <a href="https://github.com/ReactiveCocoa/ReactiveCocoa/blob/f9bc1fd2c58e0c5f9096a1c42d3e51d9c912d4e0/ReactiveCocoaFramework/ReactiveCocoa/RACSignal+Operations.h#L196-205" rel="noreferrer"><code>-then:</code></a>. The <code>-then:</code> operation essentially waits for the previous operation to complete before beginning the next.</p> <pre><code>RACSignal *signal = [RACSignal empty]; for (id entity in array) { signal = [signal then:^{ return [entity asyncOperation]; }]; } [signal subscribeCompleted:^{ // At this point, all operations have completed }]; </code></pre> <p>At this point what you have is:</p> <pre><code>[[[[RACSignal empty] then:^{ return [entity1 asyncOperation]; }] then:^{ return [entity2 asyncOperation]; }] // ... then:^{ return [entityN asyncOperation]; }] </code></pre> <p>ReactiveCocoa has helpful <a href="https://github.com/ReactiveCocoa/ReactiveCocoa/tree/master/Documentation" rel="noreferrer">documentation</a> and very well documented headers, both of which were very valuable to me when I was new.</p>
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    1. POChaining asynchronous operations from an array of objects with ReactiveCocoa
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    1. USDave Lee
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    1. POChaining asynchronous operations from an array of objects with ReactiveCocoa
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    1. COYou can use `+concat:` to achieve something similar without applying `-then:` repeatedly.
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      1. USJustin Spahr-Summers
    2. COI think I chose `+then:` to communicate that there are no values, only sequencing of operations.
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      1. USDave Lee
    3. CO`-then:` is just equivalent to `+defer:` & `-concat:` & `-ignoreValues`. You could add the latter to explicitly indicate that you don't care about the values sent. Also, note that `+concat:` is not `-concat` is not `-concat:` (though they all do very similar things).
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