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# Publishers.CombineLatest4

A publisher that receives and combines the latest elements from four publishers.

```
struct CombineLatest4<A, B, C, D> where A : Publisher, B : Publisher, C : Publisher, D : Publisher, A.Failure == B.Failure, B.Failure == C.Failure, C.Failure == D.Failure
```

## Topics

### Creating a combine latest-four publisher

[`init(_:_:_:_:)`](/documentation/Combine/Publishers/CombineLatest4/init(_:_:_:_:))

### Declaring supporting types

[`Publishers.CombineLatest4.Output`](/documentation/Combine/Publishers/CombineLatest4/Output)

The kind of values published by this publisher.

[`Publishers.CombineLatest4.Failure`](/documentation/Combine/Publishers/CombineLatest4/Failure)

The kind of errors this publisher might publish.

### Inspecting publisher properties

[`a`](/documentation/Combine/Publishers/CombineLatest4/a)

[`b`](/documentation/Combine/Publishers/CombineLatest4/b)

[`c`](/documentation/Combine/Publishers/CombineLatest4/c)

[`d`](/documentation/Combine/Publishers/CombineLatest4/d)

### Comparing publishers


---

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