1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
|
# has-value [](https://www.npmjs.com/package/has-value) [](https://npmjs.org/package/has-value) [](https://npmjs.org/package/has-value) [](https://travis-ci.org/jonschlinkert/has-value)
> 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).
### Contributors
| **Commits** | **Contributor** |
| --- | --- |
| 17 | [jonschlinkert](https://github.com/jonschlinkert) |
| 2 | [rmharrison](https://github.com/rmharrison) |
### Building docs
_(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
```
### Running tests
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
```
### Author
**Jon Schlinkert**
* [github/jonschlinkert](https://github.com/jonschlinkert)
* [twitter/jonschlinkert](https://twitter.com/jonschlinkert)
### License
Copyright © 2017, [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 May 19, 2017._
|
