# isNegativeInteger
> Test if a value is a number having a negative integer value.
## Usage
```javascript
var isNegativeInteger = require( '@stdlib/assert/is-negative-integer' );
```
#### isNegativeInteger( value )
Tests if a `value` is a `number` having a negative `integer` value.
```javascript
var Number = require( '@stdlib/number/ctor' );
var bool = isNegativeInteger( -5.0 );
// returns true
bool = isNegativeInteger( new Number( -5.0 ) );
// returns true
bool = isNegativeInteger( 5.0 );
// returns false
bool = isNegativeInteger( -3.14 );
// returns false
bool = isNegativeInteger( null );
// returns false
```
#### isNegativeInteger.isPrimitive( value )
Tests if a `value` is a primitive `number` having a negative `integer` value.
```javascript
var Number = require( '@stdlib/number/ctor' );
var bool = isNegativeInteger.isPrimitive( -3.0 );
// returns true
bool = isNegativeInteger.isPrimitive( new Number( -3.0 ) );
// returns false
```
#### isNegativeInteger.isObject( value )
Tests if a `value` is a `Number` object having a negative `integer` value.
```javascript
var Number = require( '@stdlib/number/ctor' );
var bool = isNegativeInteger.isObject( -3.0 );
// returns false
bool = isNegativeInteger.isObject( new Number( -3.0 ) );
// returns true
```
## Examples
```javascript
var Number = require( '@stdlib/number/ctor' );
var isNegativeInteger = require( '@stdlib/assert/is-negative-integer' );
var bool = isNegativeInteger( -5.0 );
// returns true
bool = isNegativeInteger( new Number( -5.0 ) );
// returns true
bool = isNegativeInteger( 0.0 );
// returns false
bool = isNegativeInteger( -3.14 );
// returns false
bool = isNegativeInteger( 5.0 );
// returns false
bool = isNegativeInteger( '-5' );
// returns false
bool = isNegativeInteger( null );
// returns false
```