# youch-core

> Error parser to parse an error instance into a collection of frames

Latest version **0.3.3** (published 2025-07-04) · MIT license · 0 weekly downloads

## Install

```sh
npm install youch-core
pnpm add youch-core
yarn add youch-core
bun add youch-core
```

## Health

**Score 45/100 (D)** — status: maintenance-mode.

Positive: has types; esm support; no vulnerabilities; has provenance; high quality score.

Warnings: low downloads; pre 1.0.

Negative: stale; low maintenance score.

## Facts

| | |
|---|---|
| Version | 0.3.3 |
| Published | 2025-07-04 |
| First published | 2024-10-25 |
| Weekly downloads | 0 |
| License | MIT |
| TypeScript types | bundled |
| Module format | ESM + CommonJS |
| Dependencies | 2 |
| Unpacked size | 21.9 KB |
| Known vulnerabilities | 0 |
| Install scripts | no |
| Provenance | attested (GitHub Actions) |
| GitHub stars | 4 |
| Author | Harminder Virk |
| Maintainers | virk |
| Keywords | pretty-print, pretty-error |

## Links

- npm: https://www.npmjs.com/package/youch-core
- Repository: https://github.com/poppinss/youch-core
- Homepage: https://github.com/poppinss/youch-core#readme
- Issues: https://github.com/poppinss/youch-core/issues
- npm.io page: https://npm.io/package/youch-core

## Dependencies (2)

- [@poppinss/exception](https://npm.io/package/@poppinss/exception.md) ^1.2.2
- [error-stack-parser-es](https://npm.io/package/error-stack-parser-es.md) ^1.0.5

## Alternatives

- [@sentry/react-native](https://npm.io/package/@sentry/react-native.md) — 2.6M weekly downloads
- [@ardatan/aggregate-error](https://npm.io/package/@ardatan/aggregate-error.md) — 708.1K weekly downloads
- [custom-error-generator](https://npm.io/package/custom-error-generator.md) — 2.0K weekly downloads
- [@technik-sde/prosemirror-recreate-transform](https://npm.io/package/@technik-sde/prosemirror-recreate-transform.md) — 1.5K weekly downloads
- [@suchipi/error-utils](https://npm.io/package/@suchipi/error-utils.md) — 78 weekly downloads

## Recent versions

- 0.3.3 (latest) — 2025-07-04
- 0.3.2 — 2025-03-07
- 0.3.1 — 2024-12-28
- 0.3.0 — 2024-11-23
- 0.2.6 — 2024-11-15
- 0.2.5 — 2024-11-15
- 0.2.4 — 2024-11-12
- 0.2.3 — 2024-11-11
- 0.2.2 — 2024-11-10
- 0.2.1 — 2024-11-07
- 0.2.0 — 2024-11-06
- 0.1.0 — 2024-10-25

## README

# youch-core

> Error parser to parse an error instance into a collection of frames

<br />

[![gh-workflow-image]][gh-workflow-url] [![npm-image]][npm-url] ![][typescript-image] [![license-image]][license-url]

## Introduction

The `youch-core` package contains the Error parser used by [youch](https://github.com/poppinss/youch) to pretty print Errors on the Web and the terminal.

It is a low-level package and you will only use it if you want to create your own Error printer while re-using the core Error parsing logic.

## Installation

Install the package from the npm registry as follows.

```sh
npm i @poppinss/dumper
```

```sh
yarn add @poppinss/dumper
```

```sh
pnpm add @poppinss/dumper
```

## Usage

You may parse an error using the `ErrorParser.parse` method. The `parse` method accepts the erorr object and returns back a Promise with [ParsedError](https://github.com/poppinss/youch-core/blob/0.x/src/types.ts#L21).

```ts
import { ErrorParser } from 'youch-core'

/**
 * Error object to parse
 */
const error = new Error('Something went wrong')

/**
 * Create parser instance and parse the error
 */
const parser = new ErrorParser()
const parsedError = await parser.parse(error)
```

The `parsedError.frames` property is an array of stack frames with the **filename**, **line number** and the **source code snippet** for the given frame in the stack.

```ts
parsedError.frames.forEach((frame) => {
  console.log(`${frame.type}: ${frame.fileName}:${frame.lineNumber}`)
})
```

### Using a custom source code loader

The `ErrorParser` reads the source code of files within the stack trace using the Node.js `fs` module. However, you can override this default and provide a custom source loader using the `parser.defineSourceLoader` method.

> [!NOTE]
> The `defineSourceLoader` method is called for every frame within the stack traces. Therefore, you must perform the necessary checks before attempting to read the source code of a file.
> For example, you must not attempt to read the source code for fileNames pointing to native code.

```ts
const parser = new ErrorParser()

parser.defineSourceLoader(async (stackFrame) => {
  if (stackFrame.type !== 'native') {
    stackFrame.source = await someFunctionToGetFileSource(stackFrame.fileName)
  }
})
```

## Contributing

One of the primary goals of Poppinss is to have a vibrant community of users and contributors who believes in the principles of the framework.

We encourage you to read the [contribution guide](https://github.com/poppinss/.github/blob/main/docs/CONTRIBUTING.md) before contributing to the framework.

## Code of Conduct

In order to ensure that the Poppinss community is welcoming to all, please review and abide by the [Code of Conduct](https://github.com/poppinss/.github/blob/main/docs/CODE_OF_CONDUCT.md).

## License

The `youch-core` package is open-sourced software licensed under the [MIT license](LICENSE.md).

[gh-workflow-image]: https://img.shields.io/github/actions/workflow/status/poppinss/youch-core/checks.yml?style=for-the-badge
[gh-workflow-url]: https://github.com/poppinss/youch-core/actions/workflows/checks.yml 'Github action'
[typescript-image]: https://img.shields.io/badge/Typescript-294E80.svg?style=for-the-badge&logo=typescript
[typescript-url]: "typescript"
[npm-image]: https://img.shields.io/npm/v/youch-core.svg?style=for-the-badge&logo=npm
[npm-url]: https://npmjs.org/package/youch-core 'npm'
[license-image]: https://img.shields.io/npm/l/youch-core?color=blueviolet&style=for-the-badge
[license-url]: LICENSE.md 'license'

---
_Source: https://npm.io/package/youch-core · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._