# Version Guard

Used to ensure modern CLI scripts fail silently on old node.js versions

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## Usage

Add a top-level file to your project, eg. `cli.js`, containing something like:

```javascript
require('version-guard')('./path/to/file/to/run', 14, 18);
```

## Syntax

`versionGuard(filePath, minMajor, [minMinor])`

* **filePath** - a path to the modern file that should be run
* **minMajor** - the lowest major Node.js version that should be allowed to run the file
* **[minMinor]** - the lowest minor version of `minMajor` that should be allowed to run the file

On supported versions imports and runs `filePath` using the [dynamic `import()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/import) (supporting both ESM and CJS modules).

On non-supported versions, fails silently with an error message.

Apart from checking current node version this command also looks up the main project's `package.json` and checks that the `engines.node` in it mentions the same version number as is sent to this command. To ensure that maintainers doesn't forget to update one of the two and thus the two diverging.

## Notes

This project itself is a CJS project as the entire point is to work on incredibly old node.js versions.

## Used by

* [`installed-check`](https://www.npmjs.com/package/installed-check)
* [`standard`](https://www.npmjs.com/package/standard)