@stdlib/error/tools/pkg2id/README.md

Errors.

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# pkg2id

> Return the error identifier prefix associated with a specified package name.

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## Usage

```javascript
var pkg2id = require( '@stdlib/error/tools/pkg2id' );
```

#### pkg2id( pkg )

Returns the error identifier prefix associated with a specified package name.

```javascript
var v = pkg2id( '@stdlib/math/base/special/sin' );
// returns '0YK'
```

If provided an unrecognized `pkg`, the function returns `null`.

```javascript
var v = pkg2id( 'unrecognized_pkg_beep_boop_bop_bip' );
// returns null
```

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## Notes

-   The function supports providing both internal and standalone package names.

    ```javascript
    var v = pkg2id( '@stdlib/math-base-special-sin' );
    // returns '0YK'
    ```

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## Examples

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

```javascript
var formatProdErrorMessage = require( '@stdlib/error/tools/fmtprodmsg' );
var pkg2id = require( '@stdlib/error/tools/pkg2id' );

var prefix = pkg2id( '@stdlib/math/base/special/sin' );
var errorCode = '23';
var code = prefix + errorCode;

var msg = formatProdErrorMessage( code );
console.log( msg );
// => <string>
```

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* * *

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## CLI

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### Usage

```text
Usage: stdlib-pkg2id [options] <pkg>

Options:

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

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### Examples

```bash
$ stdlib-pkg2id '@stdlib/math/base/special/sin'
0YK
```

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</section>

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## License

The data files (databases) are licensed under an [Open Data Commons Public Domain Dedication & License 1.0][pddl-1.0] and their contents are licensed under [Creative Commons Zero v1.0 Universal][cc0]. The software is licensed under [Apache License, Version 2.0][apache-license].

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[pddl-1.0]: http://opendatacommons.org/licenses/pddl/1.0/

[cc0]: https://creativecommons.org/publicdomain/zero/1.0

[apache-license]: https://www.apache.org/licenses/LICENSE-2.0

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