> Returns true if a value exists, false if empty. Works with deeply nested values using object paths.
## Install
Install with [npm](https://www.npmjs.com/):
```sh
$ npm install --save has-value
```
**Works for:**
* booleans
* functions
* numbers
* strings
* nulls
* object
* arrays
## Usage
Works with property values (supports object-path notation, like `foo.bar`) or a single value:
```js
var hasValue = require('has-value');
hasValue('foo');
hasValue({foo: 'bar'}, 'foo');
hasValue({a: {b: {c: 'foo'}}}, 'a.b.c');
//=> true
hasValue('');
hasValue({foo: ''}, 'foo');
//=> false
hasValue(0);
hasValue(1);
hasValue({foo: 0}, 'foo');
hasValue({foo: 1}, 'foo');
hasValue({foo: null}, 'foo');
hasValue({foo: {bar: 'a'}}}, 'foo');
hasValue({foo: {bar: 'a'}}}, 'foo.bar');
//=> true
hasValue({foo: {}}}, 'foo');
hasValue({foo: {bar: {}}}}, 'foo.bar');
hasValue({foo: undefined}, 'foo');
//=> false
hasValue([]);
hasValue([[]]);
hasValue([[], []]);
hasValue([undefined]);
hasValue({foo: []}, 'foo');
//=> false
hasValue([0]);
hasValue([null]);
hasValue(['foo']);
hasValue({foo: ['a']}, 'foo');
//=> true
hasValue(function() {})
hasValue(function(foo) {})
hasValue({foo: function(foo) {}}, 'foo');
hasValue({foo: function() {}}, 'foo');
//=> true
hasValue(true);
hasValue(false);
hasValue({foo: true}, 'foo');
hasValue({foo: false}, 'foo');
//=> true
```
## isEmpty
To do the opposite and test for empty values, do:
```js
function isEmpty(o) {
return !hasValue.apply(hasValue, arguments);
}
```
## Release history
### v1.0.0
*`zero` always returns true
*`array` now recurses, so that an array of empty arrays will return `false`
*`null` now returns true
## About
### Related projects
* [define-property](https://www.npmjs.com/package/define-property): Define a non-enumerable property on an object. | [homepage](https://github.com/jonschlinkert/define-property "Define a non-enumerable property on an object.")
* [get-value](https://www.npmjs.com/package/get-value): Use property paths (`a.b.c`) to get a nested value from an object. | [homepage](https://github.com/jonschlinkert/get-value "Use property paths (`a.b.c`) to get a nested value from an object.")
* [set-value](https://www.npmjs.com/package/set-value): Create nested values and any intermediaries using dot notation (`'a.b.c'`) paths. | [homepage](https://github.com/jonschlinkert/set-value "Create nested values and any intermediaries using dot notation (`'a.b.c'`) paths.")
* [unset-value](https://www.npmjs.com/package/unset-value): Delete nested properties from an object using dot notation. | [homepage](https://github.com/jonschlinkert/unset-value "Delete nested properties from an object using dot notation.")
### Contributing
Pull requests and stars are always welcome. For bugs and feature requests, [please create an issue](../../issues/new).
_(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:
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:
