package-missing/Readme.md

This very simple but incredibly useful package contains a Constructor for the `PackageMissingError`.

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# package-missing

This, very simple but incredibly useful package contains a Constructor for the `PackageMissingError`.

## Usage

```javascript
const PackageMissingError = require('package-missing')

// What would work if another package was installed?
const task = 'Can not parse the file test.yml'

// What packages can be installed to make this work?
const recommendedPackages = [ 'js-yaml', 'yaml' ]

const error = new PackageMissingError(task, recommendedPackages)

// You can test for this code
error.code === 'EPACKAGEMISSING'

// ... or for the package-missing-error
error instanceof PackageMissingError

// The input is available to be processed
error.task === task
error.recommendedPackages === recommendedPackages

// The message recommends to install the mentioned packages
error.message === error.code + ': ' + error.message + '\n'
    + 'This error can be easily fixed by running ONE of the following commands:\n'
    + recommendedPackages.map((pkg) => '- $ npm install ' + pkg + ' --save').join('\n')

// The error comes with a stack, but if you don't like it ...
typeof error.stack === 'string'
```

## License
ISC