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# {%= name %} {%= badge("fury") %} {%= badge("travis") %}
> {%= description %}
## Install
{%= include("install-npm", {save: true}) %}
## Usage
```js
var isDataDesc = require('{%= name %}');
```
## Examples
`true` when the descriptor has valid properties with valid values.
```js
// `value` can be anything
isDataDesc({value: 'foo'})
isDataDesc({value: function() {}})
isDataDesc({value: true})
//=> true
```
`false` when not an object
```js
isDataDesc('a')
//=> false
isDataDesc(null)
//=> false
isDataDesc([])
//=> false
```
`false` when the object has invalid properties
```js
isDataDesc({value: 'foo', bar: 'baz'})
//=> false
isDataDesc({value: 'foo', bar: 'baz'})
//=> false
isDataDesc({value: 'foo', get: function(){}})
//=> false
isDataDesc({get: function(){}, value: 'foo'})
//=> false
```
`false` when a value is not the correct type
```js
isDataDesc({value: 'foo', enumerable: 'foo'})
//=> false
isDataDesc({value: 'foo', configurable: 'foo'})
//=> false
isDataDesc({value: 'foo', writable: 'foo'})
//=> false
```
## Valid properties
The only valid data descriptor properties are the following:
- `configurable` (required)
- `enumerable` (required)
- `value` (optional)
- `writable` (optional)
To be a valid data descriptor, either `value` or `writable` must be defined.
**Invalid properties**
A descriptor may have additional _invalid_ properties (an error will **not** be thrown).
```js
var foo = {};
Object.defineProperty(foo, 'bar', {
enumerable: true,
whatever: 'blah', // invalid, but doesn't cause an error
get: function() {
return 'baz';
}
});
console.log(foo.bar);
//=> 'baz'
```
## Related projects
{%= related(verb.related.list, {remove: name}) %}
## Running tests
{%= include("tests") %}
## Contributing
{%= include("contributing") %}
## Author
{%= include("author") %}
## License
{%= copyright() %}
{%= license %}
***
{%= include("footer") %}
|
