@stdlib/error/tools/msg2id/README.md

Errors.

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# msg2id

> Return a two-character error identifier corresponding to a provided error message.

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## Usage

```javascript
var msg2id = require( '@stdlib/error/tools/msg2id' );
```

#### msg2id( msg )

Returns a two-character error identifier corresponding to a provided error message.

```javascript
var v = msg2id( 'invalid value. `%s` must be a number. Value: `%s`.' );
// e.g., returns '6d'
```

If provided an unrecognized error message, the function returns `null`.

```javascript
var v = msg2id( 'beep boop baz' );
// returns null
```

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## Examples

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

```javascript
var msg2id = require( '@stdlib/error/tools/msg2id' );

var list;
var v;
var i;

list = [
    'invalid argument. First argument must be a number and not `NaN`. Value: `%s`.',
    'invalid argument. First argument must be a positive integer. Value: `%s`.'
];

for ( i = 0; i < list.length; i++ ) {
    v = list[ i ];
    console.log( 'msg: "%s". id: "%s".', v, msg2id( v ) );
}
```

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* * *

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## CLI

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### Usage

```text
Usage: stdlib-msg2id [options] <msg>

Options:

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

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### Examples

```bash
$ stdlib-msg2id 'invalid value. `%s` must be a number. Value: `%s`.'
6d
```

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