---
title: "init(upstream:prefix:file:line:)"
framework: combine
role: symbol
role_heading: Initializer
path: "combine/publishers/assertnofailure/init(upstream:prefix:file:line:)"
---

# init(upstream:prefix:file:line:)

Creates a publisher that raises a fatal error upon receiving any failure, and otherwise republishes all received input.

## Declaration

```swift
init(upstream: Upstream, prefix: String, file: StaticString, line: UInt)
```

## Parameters

- `upstream`: The publisher from which this publisher receives elements.
- `prefix`: The string used at the beginning of the fatal error message.
- `file`: The filename used in the error message.
- `line`: The line number used in the error message.