# shift
> Remove and return the first element of a collection.
## Usage
```javascript
var shift = require( '@stdlib/utils/shift' );
```
#### shift( collection )
Removes and returns the first element of a `collection`. A `collection` may be either an [`Array`][mdn-array], [`Typed Array`][mdn-typed-array], or an array-like [`Object`][mdn-object] (i.e., an [`Object`][mdn-object] having a valid writable `length` property).
```javascript
var arr = [ 1.0, 2.0, 3.0, 4.0, 5.0 ];
var out = shift( arr );
// returns [ [ 2.0, 3.0, 4.0, 5.0 ], 1.0 ]
var bool = ( out[ 0 ] === arr );
// returns true
var lastValue = out[ 1 ];
// returns 1.0
```
In contrast to [`Array.prototype.shift`][mdn-array-shift] which returns only the removed element, the function also returns the shortened collection. For [typed arrays][mdn-typed-array] having a length greater than `0`, the returned collection is a new [typed array][mdn-typed-array] view.
```javascript
var Float64Array = require( '@stdlib/array/float64' );
var arr = new Float64Array( 2 );
arr[ 0 ] = 1.0;
arr[ 1 ] = 2.0;
var out = shift( arr );
// returns [ [ 2.0 ], 1.0 ]
var bool = ( out[ 0 ] === arr );
// returns false
bool = ( out[ 0 ].buffer === arr.buffer );
// returns true
var lastValue = out[ 1 ];
// returns 1.0
```
## Notes
- When provided a [typed array][mdn-typed-array], the function does **not** change the underlying [`ArrayBuffer`][mdn-arraybuffer]. The function returns a new [typed array][mdn-typed-array] view whose length is one less than the input [typed array][mdn-typed-array] length. Accordingly, the function does **not** reduce the memory footprint of an input [typed array][mdn-typed-array].
## Examples
```javascript
var Float64Array = require( '@stdlib/array/float64' );
var shift = require( '@stdlib/utils/shift' );
var arr;
var out;
var i;
arr = new Float64Array( 100 );
for ( i = 0; i < 100; i++ ) {
out = shift( arr );
arr = out[ 0 ];
console.log( 'Length: %d', arr.length );
}
console.log( arr );
```
[mdn-array]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array
[mdn-array-shift]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/shift
[mdn-typed-array]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Typed_arrays
[mdn-arraybuffer]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/ArrayBuffer
[mdn-object]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object