212 lines
6.0 KiB
Markdown
212 lines
6.0 KiB
Markdown
# has-values [![NPM version](https://img.shields.io/npm/v/has-values.svg?style=flat)](https://www.npmjs.com/package/has-values) [![NPM monthly downloads](https://img.shields.io/npm/dm/has-values.svg?style=flat)](https://npmjs.org/package/has-values) [![NPM total downloads](https://img.shields.io/npm/dt/has-values.svg?style=flat)](https://npmjs.org/package/has-values) [![Linux Build Status](https://img.shields.io/travis/jonschlinkert/has-values.svg?style=flat&label=Travis)](https://travis-ci.org/jonschlinkert/has-values)
|
|
|
|
> Returns true if any values exist, false if empty. Works for booleans, functions, numbers, strings, nulls, objects and arrays.
|
|
|
|
Please consider following this project's author, [Jon Schlinkert](https://github.com/jonschlinkert), and consider starring the project to show your :heart: and support.
|
|
|
|
## Install
|
|
|
|
Install with [npm](https://www.npmjs.com/):
|
|
|
|
```sh
|
|
$ npm install --save has-values
|
|
```
|
|
|
|
## Usage
|
|
|
|
```js
|
|
const has = require('has-values');
|
|
```
|
|
|
|
Create an `isEmpty` function by returning the inverse of the result from has-values:
|
|
|
|
```js
|
|
const isEmpty = val => !has(val);
|
|
```
|
|
|
|
## Supported types
|
|
|
|
### Arrays
|
|
|
|
```js
|
|
console.log(has(['a'])); //=> true
|
|
console.log(has([0])); //=> true
|
|
console.log(has([[[]]])); //=> false
|
|
console.log(has([[], []])); //=> false
|
|
console.log(has([])); //=> false
|
|
```
|
|
|
|
### Booleans
|
|
|
|
```js
|
|
console.log(has(true)); //=> true
|
|
console.log(has(false)); //=> true
|
|
```
|
|
|
|
### Buffers
|
|
|
|
```js
|
|
console.log(has(new Buffer())); //=> false
|
|
console.log(has(new Buffer('foo'))); //=> true
|
|
```
|
|
|
|
### Dates
|
|
|
|
Dates are always true.
|
|
|
|
```js
|
|
console.log(has(new Date())); //=> true
|
|
```
|
|
|
|
### Errors
|
|
|
|
Returns `false` if `err.message` is an empty string.
|
|
|
|
```js
|
|
console.log(has(new Error())); //=> false
|
|
console.log(has(new Error('foo'))); //=> true
|
|
```
|
|
|
|
### Functions
|
|
|
|
Functions are always true.
|
|
|
|
```js
|
|
console.log(has(function(foo) {})); //=> true
|
|
console.log(has(function() {})); //=> true
|
|
```
|
|
|
|
### Maps
|
|
|
|
```js
|
|
console.log(has(new Map())); //=> false
|
|
console.log(has(new Map([['foo', 'bar']]))); //=> true
|
|
```
|
|
|
|
### Null
|
|
|
|
`null` is always true, as it's assumed that this is a user-defined value, versus `undefined` which is not.
|
|
|
|
```js
|
|
console.log(has(null)); //=> true
|
|
```
|
|
|
|
### Objects
|
|
|
|
```js
|
|
console.log(has({})); //=> false
|
|
console.log(has({ a: 'a' }})); //=> true
|
|
console.log(has({ foo: undefined })); //=> false
|
|
console.log(has({ foo: null })); //=> true
|
|
```
|
|
|
|
### Numbers
|
|
|
|
```js
|
|
console.log(has(1)); //=> true
|
|
console.log(has(0)); //=> true
|
|
```
|
|
|
|
### Regular expressions
|
|
|
|
```js
|
|
console.log(has(new RegExp())); //=> false
|
|
console.log(has(new RegExp('foo'))); //=> true
|
|
```
|
|
|
|
### Sets
|
|
|
|
```js
|
|
console.log(has(new Set())); //=> false
|
|
console.log(has(new Set(['foo', 'bar']))); //=> true
|
|
```
|
|
|
|
### Strings
|
|
|
|
```js
|
|
console.log(has('a')); //=> true
|
|
console.log(has('')); //=> false
|
|
```
|
|
|
|
## Undefined
|
|
|
|
```js
|
|
console.log(has()); //=> false
|
|
console.log(has(void 0)); //=> false
|
|
console.log(has(undefined)); //=> false
|
|
```
|
|
|
|
## Release history
|
|
|
|
### v2.0.0
|
|
|
|
* no longer supports numbers as a string
|
|
* optimizations
|
|
* adds support for `regex` and `buffer`
|
|
|
|
### v1.0.0
|
|
|
|
* adds support for `Map` and `Set`
|
|
* `zero` always returns true
|
|
* `array` now recurses, so that an array of empty arrays will return `false`
|
|
* `null` now returns true
|
|
|
|
## About
|
|
|
|
<details>
|
|
<summary><strong>Contributing</strong></summary>
|
|
|
|
Pull requests and stars are always welcome. For bugs and feature requests, [please create an issue](../../issues/new).
|
|
|
|
</details>
|
|
|
|
<details>
|
|
<summary><strong>Running Tests</strong></summary>
|
|
|
|
Running and reviewing unit tests is a great way to get familiarized with a library and its API. You can install dependencies and run tests with the following command:
|
|
|
|
```sh
|
|
$ npm install && npm test
|
|
```
|
|
|
|
</details>
|
|
|
|
<details>
|
|
<summary><strong>Building docs</strong></summary>
|
|
|
|
_(This project's readme.md is generated by [verb](https://github.com/verbose/verb-generate-readme), please don't edit the readme directly. Any changes to the readme must be made in the [.verb.md](.verb.md) readme template.)_
|
|
|
|
To generate the readme, run the following command:
|
|
|
|
```sh
|
|
$ npm install -g verbose/verb#dev verb-generate-readme && verb
|
|
```
|
|
|
|
</details>
|
|
|
|
### Related projects
|
|
|
|
You might also be interested in these projects:
|
|
|
|
* [has-value](https://www.npmjs.com/package/has-value): Returns true if a value exists, false if empty. Works with deeply nested values using… [more](https://github.com/jonschlinkert/has-value) | [homepage](https://github.com/jonschlinkert/has-value "Returns true if a value exists, false if empty. Works with deeply nested values using object paths.")
|
|
* [is-number](https://www.npmjs.com/package/is-number): Returns true if the value is a number. comprehensive tests. | [homepage](https://github.com/jonschlinkert/is-number "Returns true if the value is a number. comprehensive tests.")
|
|
* [is-plain-object](https://www.npmjs.com/package/is-plain-object): Returns true if an object was created by the `Object` constructor. | [homepage](https://github.com/jonschlinkert/is-plain-object "Returns true if an object was created by the `Object` constructor.")
|
|
* [isobject](https://www.npmjs.com/package/isobject): Returns true if the value is an object and not an array or null. | [homepage](https://github.com/jonschlinkert/isobject "Returns true if the value is an object and not an array or null.")
|
|
* [kind-of](https://www.npmjs.com/package/kind-of): Get the native type of a value. | [homepage](https://github.com/jonschlinkert/kind-of "Get the native type of a value.")
|
|
|
|
### Author
|
|
|
|
**Jon Schlinkert**
|
|
|
|
* [linkedin/in/jonschlinkert](https://linkedin.com/in/jonschlinkert)
|
|
* [github/jonschlinkert](https://github.com/jonschlinkert)
|
|
* [twitter/jonschlinkert](https://twitter.com/jonschlinkert)
|
|
|
|
### License
|
|
|
|
Copyright © 2018, [Jon Schlinkert](https://github.com/jonschlinkert).
|
|
Released under the [MIT License](LICENSE).
|
|
|
|
***
|
|
|
|
_This file was generated by [verb-generate-readme](https://github.com/verbose/verb-generate-readme), v0.6.0, on January 30, 2018._ |