@stdlib/assert/is-relative-uri/README.md

Standard assertion utilities.

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# isRelativeURI

> Test whether a value is a relative [URI][uri].

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## Usage

```javascript
var isRelativeURI = require( '@stdlib/assert/is-relative-uri' );
```

#### isRelativeURI( value )

Tests whether a value is a relative [URI][uri].

```javascript
var bool = isRelativeURI( 'foo/bar' );
// returns true

bool = isRelativeURI( 'https://example.com/' );
// returns false
```

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## Notes

-   For more information regarding the URI scheme, see [RFC 3986][rfc-3986] and [Wikipedia][uri].
-   On the distinction between URI, URL, and URN, see [The Difference Between URLs and URIs][difference-url-uri].

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## Examples

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```javascript
var isRelativeURI = require( '@stdlib/assert/is-relative-uri' );

var bool = isRelativeURI( './foo.js' );
// returns true

bool = isRelativeURI( '/dashboard/admin' );
// returns true

bool = isRelativeURI( 'image.png' );
// returns true

bool = isRelativeURI( 'http://www.example.com/' );
// returns false

bool = isRelativeURI( 'https://www.example.com/' );
// returns false

bool = isRelativeURI( 'ftp://ftp.is.co.za/rfc/rfc1808.txt' );
// returns false

bool = isRelativeURI( 'data:text/plain;base64,SGVsbG8sIFdvcmxkIQ%3D%3D' );
// returns false

bool = isRelativeURI( 'mailto:beep@boop.com' );
// returns false

bool = isRelativeURI( null );
// returns false
```

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* * *

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## CLI

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### Usage

```text
Usage: is-relative-uri [options] [<uri>]

Options:

  -h,    --help                Print this message.
  -V,    --version             Print the package version.
         --split sep           Delimiter for stdin data. Default: '/\\r?\\n/'.
```

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### Examples

```bash
$ is-relative-uri google.com
true
```

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

```bash
$ echo -n 'https://google.com' | is-relative-uri
false
```

By default, when used as a [standard stream][standard-streams], the implementation assumes newline-delimited data. To specify an alternative delimiter, set the `split` option.

```bash
$ echo -n 'https://google.com\tbeep' | is-absolute-uri --split '\t'
false
true
```

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* * *

## See Also

-   <span class="package-name">[`@stdlib/assert/is-uri`][@stdlib/assert/is-uri]</span><span class="delimiter">: </span><span class="description">test if a value is a URI.</span>

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[uri]: https://en.wikipedia.org/wiki/URI_scheme

[rfc-3986]: https://tools.ietf.org/html/rfc3986

[difference-url-uri]: https://danielmiessler.com/study/url-uri/

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

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[@stdlib/assert/is-uri]: https://github.com/stdlib-js/assert/tree/main/is-uri

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