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# Publishers.Concatenate

A publisher that emits all of one publisher’s elements before those from another publisher.

```
struct Concatenate<Prefix, Suffix> where Prefix : Publisher, Suffix : Publisher, Prefix.Failure == Suffix.Failure, Prefix.Output == Suffix.Output
```

## Topics

### Creating a concatenate publisher

[`init(prefix:suffix:)`](/documentation/Combine/Publishers/Concatenate/init(prefix:suffix:))

Creates a publisher that emits all of one publisher’s elements before those from another publisher.

### Declaring supporting types

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

The kind of values published by this publisher.

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

The kind of errors this publisher might publish.

### Inspecting publisher properties

[`prefix`](/documentation/Combine/Publishers/Concatenate/prefix)

The publisher to republish, in its entirety, before republishing elements from `suffix`.

[`suffix`](/documentation/Combine/Publishers/Concatenate/suffix)

The publisher to republish only after `prefix` finishes.

### Comparing publishers

[`==(_:_:)`](/documentation/Combine/Publishers/Concatenate/==(_:_:))

Returns a Boolean value that indicates whether two publishers are equivalent.


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