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# isDigitString

> Test whether a string contains only numeric digits.

<section class="usage">

## 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
```

</section>

<!-- /.usage -->

<section class="notes">

## Notes

-   For non-string values, the function returns `false`.

</section>

<!-- /.notes -->

<section class="examples">

## Examples

<!-- eslint no-undef: "error" -->

```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
```

</section>

<!-- /.examples -->

* * *

<section class="cli">

## CLI

<section class="usage">

### Usage

```text
Usage: is-digit-string [options] [<string>]

Options:

  -h,    --help                Print this message.
  -V,    --version             Print the package version.
```

</section>

<!-- /.usage -->

<section class="examples">

### Examples

```bash
$ is-digit-string 0123456789
true
```

To use as a [standard stream][standard-streams],

```bash
$ echo -n '0123456789' | is-digit-string
true
```

</section>

<!-- /.examples -->

</section>

<!-- /.cli -->

<section class="links">

[standard-streams]: https://en.wikipedia.org/wiki/Standard_streams

</section>

<!-- /.links -->