# Slice
> Slice constructor.
## Usage
```javascript
var Slice = require( '@stdlib/slice/ctor' );
```
#### Slice( \[stop] )
Returns a `Slice` instance.
```javascript
var s = new Slice();
// returns
s = new Slice();
// returns
```
The constructor accepts the following arguments:
- **stop**: ending index (exclusive). Default: `null`.
#### Slice( start, stop\[, step] )
Returns a `Slice` instance.
```javascript
var s = new Slice( 0, 10 );
// returns
s = new Slice( 0, 10, 1 );
// returns
```
The constructor accepts the following arguments:
- **start**: starting index (inclusive).
- **stop**: ending index (exclusive).
- **step**: index increment. A numeric index increment argument must be a non-zero integer value. Default: `null`.
* * *
### Properties
#### Slice.name
String value of the `Slice` constructor name.
```javascript
var str = Slice.name;
// returns 'Slice'
```
#### Slice.prototype.start
**Read-only** property returning the slice starting index.
```javascript
var s = new Slice( 10 );
// returns
var start = s.start;
// returns null
s = new Slice( 2, 10 );
// returns
start = s.start;
// returns 2
```
#### Slice.prototype.stop
**Read-only** property returning the slice ending index.
```javascript
var s = new Slice( null );
// returns
var stop = s.stop;
// returns null
s = new Slice( 10 );
// returns
stop = s.stop;
// returns 10
s = new Slice( 2, 10 );
// returns
stop = s.stop;
// returns 10
```
#### Slice.prototype.step
**Read-only** property returning the slice index increment.
```javascript
var s = new Slice( 10 );
// returns
var step = s.step;
// returns null
s = new Slice( 2, 10 );
// returns
step = s.step;
// returns null
s = new Slice( 2, 10, 1 );
// returns
step = s.step;
// returns 1
```
* * *
### Methods
#### Slice.prototype.toString()
Serializes a `Slice` as a string.
```javascript
var s = new Slice( 10 );
// returns
var str = s.toString();
// returns 'Slice(null,10,null)'
s = new Slice( 2, 10, 1 );
// returns
str = s.toString();
// returns 'Slice(2,10,1)'
```
#### Slice.prototype.toJSON()
Serializes a `Slice` as a [JSON][json] object.
```javascript
var s = new Slice( 10 );
// returns
var o = s.toJSON();
// returns { 'type': 'Slice', 'data': [ null, 10, null ] }
s = new Slice( 2, 10, 1 );
// returns
o = s.toJSON();
// returns { 'type': 'Slice', 'data': [ 2, 10, 1 ] }
```
`JSON.stringify()` implicitly calls this method when stringifying a `Slice` instance.
* * *
## Notes
- Slice arguments may be either integers, `null`, or `undefined`, where a non-integer value indicates a slice parameter which should be determined based on the slice context (e.g., when used to index into an [`ndarray`][@stdlib/ndarray/ctor]).
- Slice instances have no explicit functionality; however, they are used by [`ndarray`][@stdlib/ndarray] and other packages for creating views into multi-dimensional data structures.
* * *
## Examples
```javascript
var Slice = require( '@stdlib/slice/ctor' );
var s = new Slice( 9, -10, -1 );
// returns
var start = s.start;
console.log( 'Start: %d', start );
// => 'Start: 9'
var stop = s.stop;
console.log( 'Stop: %d', stop );
// => 'Stop: -10'
var step = s.step;
console.log( 'Step: %d', step );
// => 'Step: -1'
var str = s.toString();
console.log( str );
// => 'Slice(9,-10,-1)'
var o = s.toJSON();
console.log( JSON.stringify( o ) );
// => '{"type":"Slice","data":[9,-10,-1]}'
```
[json]: http://www.json.org/
[@stdlib/ndarray]: https://www.npmjs.com/package/@stdlib/ndarray
[@stdlib/ndarray/ctor]: https://www.npmjs.com/package/@stdlib/ndarray-ctor
[@stdlib/slice/multi]: https://github.com/stdlib-js/slice/tree/main/multi