https://github.com/shinnn/append-type

Stringify the value with appending its type: 10 → '10 (number)'
https://github.com/shinnn/append-type

error-messages javascript stringify type

Last synced: 9 months ago
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Stringify the value with appending its type: 10 → '10 (number)'

• Host: GitHub
• URL: https://github.com/shinnn/append-type
• Owner: shinnn
• License: mit-0
• Created: 2016-10-14T11:02:25.000Z (over 9 years ago)
• Default Branch: master
• Last Pushed: 2019-01-22T12:21:17.000Z (over 7 years ago)
• Last Synced: 2025-08-09T01:35:05.696Z (9 months ago)
• Topics: error-messages, javascript, stringify, type
• Language: JavaScript
• Size: 69.3 KB
• Stars: 0
• Watchers: 1
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

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README

          
# append-type

[![npm version](https://img.shields.io/npm/v/append-type.svg)](https://www.npmjs.com/package/append-type)

[![Build Status](https://travis-ci.com/shinnn/append-type.svg?branch=master)](https://travis-ci.com/shinnn/append-type)

[![Coverage Status](https://img.shields.io/coveralls/shinnn/append-type.svg)](https://coveralls.io/r/shinnn/append-type)

Stringify the value with appending its [type](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Operators/typeof): `10` → `'10 (number)'`

```javascript

import appendType from 'append-type';

appendType('123'); //=> '123 (string)'

appendType(123); //=> '123 (number)'

```

## Installation

[Use](https://docs.npmjs.com/cli/install) [npm](https://docs.npmjs.com/about-npm/).

```

npm install append-type

```

## API

```javascript

import appendType from 'append-type';

```

### appendType(*value*)

*value*: any type  

Return: `string`

Essentially, it returns `String(value) + ' (' + typeof value + ')'`.

```javascript

appendType(() => {}); //=> '() => {} (function)'

```

When it takes `null` / `undefined`, it returns `'null'` / `'undefined'`.

```javascript

appendType(null); //=> 'null'

appendType(undefined); //=> 'undefined'

```

## Example

This module is useful for making `TypeError` error messages.

```javascript

function reverse(v) {

  if (typeof v !== 'boolean') {

    throw new TypeError(`Expected a Boolean value, but got ${appendType(v)}.`);

  }

  return !v;

};

reverse(1); //=> TypeError: Expected a Boolean value, but got 1 (number).

```

## License

[MIT No Attribution](./LICENSE) © 2019 Shinnosuke Watanabe