---
title: Publishers.MapKeyPath3
framework: combine
role: symbol
role_heading: Structure
path: combine/publishers/mapkeypath3
---

# Publishers.MapKeyPath3

A publisher that publishes the values of three key paths as a tuple.

## Declaration

```swift
struct MapKeyPath3<Upstream, Output0, Output1, Output2> where Upstream : Publisher
```

## Topics

### Declaring supporting types

- [Publishers.MapKeyPath3.Output](combine/publishers/mapkeypath3/output.md)
- [Publishers.MapKeyPath3.Failure](combine/publishers/mapkeypath3/failure.md)

### Inspecting publisher properties

- [upstream](combine/publishers/mapkeypath3/upstream.md)
- [keyPath0](combine/publishers/mapkeypath3/keypath0.md)
- [keyPath1](combine/publishers/mapkeypath3/keypath1.md)
- [keyPath2](combine/publishers/mapkeypath3/keypath2.md)

## Relationships

### Conforms To

- [Publisher](combine/publisher.md)

## See Also

### Identifying properties with key paths

- [Publishers.MapKeyPath](combine/publishers/mapkeypath.md)
- [Publishers.MapKeyPath2](combine/publishers/mapkeypath2.md)