# isDigitString
> Test whether a string contains only numeric digits.
## Usage
```javascript
var isDigitString = require( '@stdlib/assert/is-digit-string' );
```
#### isDigitString( value )
Tests whether a string contains only numeric digits.
```javascript
var bool = isDigitString( '0123456789' );
// returns true
```
## Notes
- For non-string values, the function returns `false`.
## Examples
```javascript
var isDigitString = require( '@stdlib/assert/is-digit-string' );
var out = isDigitString( '0123456789' );
// returns true
out = isDigitString( '' );
// returns false
out = isDigitString( '0xffffff' );
// returns false
out = isDigitString( 123 );
// returns false
```
* * *
## CLI
### Usage
```text
Usage: is-digit-string [options] []
Options:
-h, --help Print this message.
-V, --version Print the package version.
```
### Examples
```bash
$ is-digit-string 0123456789
true
```
To use as a [standard stream][standard-streams],
```bash
$ echo -n '0123456789' | is-digit-string
true
```
[standard-streams]: https://en.wikipedia.org/wiki/Standard_streams