---
title: predicate
framework: combine
role: symbol
role_heading: Instance Property
path: combine/publishers/tryremoveduplicates/predicate
---

# predicate

An error-throwing closure to evaluate whether two elements are equivalent, for purposes of filtering.

## Declaration

```swift
let predicate: (Publishers.TryRemoveDuplicates<Upstream>.Output, Publishers.TryRemoveDuplicates<Upstream>.Output) throws -> Bool
```

## See Also

### Inspecting publisher properties

- [upstream](combine/publishers/tryremoveduplicates/upstream.md)