error-custom-class/README.md

Create custom error classes

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Create custom error classes.

# Features

- [Very simple API](#api)
- Ponyfill
  [`error.cause`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Error/cause)
  on
  [older Node.js and browsers](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Error/cause#browser_compatibility)
- Properly
  [set `error.name`](https://github.com/ehmicky/error-class-utils#seterrornameerrorclass-name)
- Fix
  [issues](https://github.com/ehmicky/error-class-utils#ensurecorrectclasserror-newtarget)
  when `Error` has been polyfilled

# Example

```js
import errorCustomClass from 'error-custom-class'

const UserError = errorCustomClass('UserError')
const DatabaseError = errorCustomClass('DatabaseError')

try {
  throw new UserError('message')
} catch (error) {
  console.log(error.name) // 'UserError'
  console.log(error instanceof UserError) // true
}
```

# Install

```bash
npm install error-custom-class
```

This package works in both Node.js >=18.18.0 and
[browsers](https://raw.githubusercontent.com/ehmicky/dev-tasks/main/src/browserslist).

This is an ES module. It must be loaded using
[an `import` or `import()` statement](https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c),
not `require()`. If TypeScript is used, it must be configured to
[output ES modules](https://www.typescriptlang.org/docs/handbook/esm-node.html),
not CommonJS.

# API

The API is designed for simplicity. For more customization,
[`error-class-utils`](https://github.com/ehmicky/error-class-utils) should be
used instead.

## errorCustomClass(errorName)

`errorName` `string`\
_Return value_: `CustomError`

Creates a custom error class.

# Related projects

- [`modern-errors`](https://github.com/ehmicky/modern-errors): Handle errors in
  a simple, stable, consistent way
- [`error-class-utils`](https://github.com/ehmicky/error-class-utils): Utilities
  to properly create error classes
- [`error-serializer`](https://github.com/ehmicky/error-serializer): Convert
  errors to/from plain objects
- [`normalize-exception`](https://github.com/ehmicky/normalize-exception):
  Normalize exceptions/errors
- [`is-error-instance`](https://github.com/ehmicky/is-error-instance): Check if
  a value is an `Error` instance
- [`merge-error-cause`](https://github.com/ehmicky/merge-error-cause): Merge an
  error with its `cause`
- [`set-error-class`](https://github.com/ehmicky/set-error-class): Properly
  update an error's class
- [`set-error-message`](https://github.com/ehmicky/set-error-message): Properly
  update an error's message
- [`wrap-error-message`](https://github.com/ehmicky/wrap-error-message):
  Properly wrap an error's message
- [`set-error-props`](https://github.com/ehmicky/set-error-props): Properly
  update an error's properties
- [`set-error-stack`](https://github.com/ehmicky/set-error-stack): Properly
  update an error's stack
- [`error-cause-polyfill`](https://github.com/ehmicky/error-cause-polyfill):
  Polyfill `error.cause`
- [`handle-cli-error`](https://github.com/ehmicky/handle-cli-error): 💣 Error
  handler for CLI applications 💥
- [`log-process-errors`](https://github.com/ehmicky/log-process-errors): Show
  some ❤ to Node.js process errors
- [`error-http-response`](https://github.com/ehmicky/error-http-response):
  Create HTTP error responses
- [`winston-error-format`](https://github.com/ehmicky/winston-error-format): Log
  errors with Winston

# Support

For any question, _don't hesitate_ to [submit an issue on GitHub](../../issues).

Everyone is welcome regardless of personal background. We enforce a
[Code of conduct](CODE_OF_CONDUCT.md) in order to promote a positive and
inclusive environment.

# Contributing

This project was made with ❤️. The simplest way to give back is by starring and
sharing it online.

If the documentation is unclear or has a typo, please click on the page's `Edit`
button (pencil icon) and suggest a correction.

If you would like to help us fix a bug or add a new feature, please check our
[guidelines](CONTRIBUTING.md). Pull requests are welcome!

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