# isBinaryString
> Test if a value is a binary string.
## Usage
```javascript
var isBinaryString = require( '@stdlib/assert/is-binary-string' );
```
#### isBinaryString( value )
Tests if a `value` is a binary `string`; i.e., a character sequence of `1`'s and `0`'s.
```javascript
var bool = isBinaryString( '1000101' );
// returns true
bool = isBinaryString( 'beep' );
// returns false
bool = isBinaryString( '' );
// returns false
```
## Examples
```javascript
var isBinaryString = require( '@stdlib/assert/is-binary-string' );
var bool = isBinaryString( '1' );
// returns true
bool = isBinaryString( '0' );
// returns true
bool = isBinaryString( '101010101001' );
// returns true
bool = isBinaryString( '' );
// returns false
bool = isBinaryString( 'beep' );
// returns false
bool = isBinaryString( null );
// returns false
```
* * *
## CLI
### Usage
```text
Usage: is-binary-string [options] []
Options:
-h, --help Print this message.
-V, --version Print the package version.
```
### Examples
```bash
$ is-binary-string 01234
false
```
To use as a [standard stream][standard-streams],
```bash
$ echo -n '0110' | is-binary-string
true
```
[standard-streams]: https://en.wikipedia.org/wiki/Standard_streams