https://github.com/wooorm/fault
Functional errors with formatted output
https://github.com/wooorm/fault
error format prinft
Last synced: 9 months ago
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Functional errors with formatted output
- Host: GitHub
- URL: https://github.com/wooorm/fault
- Owner: wooorm
- License: mit
- Created: 2015-03-03T16:04:00.000Z (almost 11 years ago)
- Default Branch: main
- Last Pushed: 2022-11-20T11:59:00.000Z (about 3 years ago)
- Last Synced: 2025-04-11T03:05:03.015Z (9 months ago)
- Topics: error, format, prinft
- Language: JavaScript
- Homepage:
- Size: 61.5 KB
- Stars: 17
- Watchers: 3
- Forks: 0
- Open Issues: 0
-
Metadata Files:
- Readme: readme.md
- Funding: funding.yml
- License: license
Awesome Lists containing this project
README
# fault
[![Build][build-badge]][build]
[![Coverage][coverage-badge]][coverage]
[![Downloads][downloads-badge]][downloads]
[![Size][size-badge]][size]
Functional errors with formatted output.
## Contents
* [What is this?](#what-is-this)
* [When should I use this?](#when-should-i-use-this)
* [Install](#install)
* [Use](#use)
* [API](#api)
* [`fault(format?[, values…])`](#faultformat-values)
* [Types](#types)
* [Compatibility](#compatibility)
* [Security](#security)
* [Related](#related)
* [Contribute](#contribute)
* [License](#license)
## What is this?
This package adds printf-like interpolation to errors.
## When should I use this?
This package useful when you frequently display parameters in error messages
and manual string concatenation is becoming verbose.
## Install
This package is [ESM only][esm].
In Node.js (version 14.14+, 16.0+), install with [npm][]:
```sh
npm install fault
```
In Deno with [`esm.sh`][esmsh]:
```js
import {fault} from 'https://esm.sh/fault@2'
```
In browsers with [`esm.sh`][esmsh]:
```html
import {fault} from 'https://esm.sh/fault@2?bundle'
```
## Use
```js
import {fault} from 'fault'
throw fault('Hello %s!', 'Eric')
```
Yields:
```text
Error: Hello Eric!
at FormattedError (~/node_modules/fault/index.js:30:12)
at Object. (~/example.js:3:7)
…
```
Or, format a float in a type error:
```js
import {fault} from 'fault'
throw fault.type('Who doesn’t like %f? 🍰', Math.PI)
```
Yields:
```text
TypeError: Who doesn’t like 3.141593? 🍰
at Function.FormattedError [as type] (~/node_modules/fault/index.js:30:12)
at Object. (~/example.js:3:7)
```
## API
This package exports the identifiers `fault` and `create`.
There is no default export.
### `fault(format?[, values…])`
Create an error with a printf-like formatted message.
###### Parameters
* `format` (`string`, optional)
— template string
* `values` (`*`, optional)
— values to render in `format`
###### Returns
An [`Error`][error] instance.
###### Formatters
The following formatters are supported in `format`:
* `%s` — string
* `%b` — binary
* `%c` — character
* `%d` — decimal
* `%f` — floating point
* `%o` — octal
* `%x` — lowercase hexadecimal
* `%X` — uppercase hexadecimal
* `%` followed by any other character, prints that character
See [`samsonjs/format`][fmt] for argument parsing.
###### Other errors
* `fault.eval(format?[, values…])` — [EvalError][]
* `fault.range(format?[, values…])` — [RangeError][]
* `fault.reference(format?[, values…])` — [ReferenceError][]
* `fault.syntax(format?[, values…])` — [SyntaxError][]
* `fault.type(format?[, values…])` — [TypeError][]
* `fault.uri(format?[, values…])` — [URIError][]
#### `create(Constructor)`
Factory to create instances of `ErrorConstructor` with support for formatting.
Used internally to wrap the global error constructors and exposed for custom
errors.
Returns a function just like `fault`.
## Types
This package is fully typed with [TypeScript][].
It exports no additional types.
## Compatibility
This package is at least compatible with all maintained versions of Node.js.
As of now, that is Node.js 14.14+ and 16.0+.
It also works in Deno and modern browsers.
## Security
This package is safe.
## Related
* [`wooorm/bail`](https://github.com/wooorm/bail)
— throw if given an error
## Contribute
Yes please!
See [How to Contribute to Open Source][contribute].
## License
[MIT][license] © [Titus Wormer][author]
[build-badge]: https://github.com/wooorm/fault/workflows/main/badge.svg
[build]: https://github.com/wooorm/fault/actions
[coverage-badge]: https://img.shields.io/codecov/c/github/wooorm/fault.svg
[coverage]: https://codecov.io/github/wooorm/fault
[downloads-badge]: https://img.shields.io/npm/dm/fault.svg
[downloads]: https://www.npmjs.com/package/fault
[size-badge]: https://img.shields.io/bundlephobia/minzip/fault.svg
[size]: https://bundlephobia.com/result?p=fault
[npm]: https://docs.npmjs.com/cli/install
[esmsh]: https://esm.sh
[license]: license
[author]: https://wooorm.com
[esm]: https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c
[typescript]: https://www.typescriptlang.org
[contribute]: https://opensource.guide/how-to-contribute/
[fmt]: https://github.com/samsonjs/format
[error]: https://developer.mozilla.org/JavaScript/Reference/Global_Objects/Error
[evalerror]: https://developer.mozilla.org/JavaScript/Reference/Global_Objects/EvalError
[rangeerror]: https://developer.mozilla.org/JavaScript/Reference/Global_Objects/RangeError
[referenceerror]: https://developer.mozilla.org/JavaScript/Reference/Global_Objects/ReferenceError
[syntaxerror]: https://developer.mozilla.org/JavaScript/Reference/Global_Objects/SyntaxError
[typeerror]: https://developer.mozilla.org/JavaScript/Reference/Global_Objects/TypeError
[urierror]: https://developer.mozilla.org/JavaScript/Reference/Global_Objects/URIError.