CityBEM-CityLayers-SaeedRay.../node_modules/hard-rejection/readme.md

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# hard-rejection [![Build Status](https://travis-ci.org/sindresorhus/hard-rejection.svg?branch=master)](https://travis-ci.org/sindresorhus/hard-rejection)
> Make unhandled promise rejections fail hard right away instead of the default [silent fail](https://gist.github.com/benjamingr/0237932cee84712951a2)
Promises fail silently if you don't attach a `.catch()` handler.
This module exits the process with an error message right away when an unhandled rejection is encountered.<br>
**Note: That might not be desirable as unhandled rejections can be [handled at a future point in time](https://nodejs.org/api/process.html#process_event_unhandledrejection), although not common. You've been warned.**
Intended for top-level long-running processes like servers, **but not in reusable modules.**<br>
For command-line apps and tests, see [`loud-rejection`](https://github.com/sindresorhus/loud-rejection).
## Install
```
$ npm install hard-rejection
```
## Usage
```js
const hardRejection = require('hard-rejection');
const promiseFunction = require('some-promise-fn');
// Install the handler
hardRejection();
promiseFunction();
```
Without this module it's more verbose and you might even miss some that will fail silently:
```js
const promiseFunction = require('some-promise-fn');
function error(error) {
console.error(error.stack);
process.exit(1);
}
promiseFunction().catch(error);
```
### Register script
Alternatively to the above, you may simply require `hard-rejection/register` and the handler will be automagically installed for you.
This is handy for ES2015 imports:
```js
import 'hard-rejection/register';
```
## API
### hardRejection([log])
#### log
Type: `Function`<br>
Default: `console.error`
Custom logging function to print the rejected promise. Receives the error stack.
## Related
- [loud-rejection](https://github.com/sindresorhus/loud-rejection) - Make unhandled promise rejections fail loudly instead of the default silent fail
- [More…](https://github.com/sindresorhus/promise-fun)
## License
MIT © [Sindre Sorhus](https://sindresorhus.com)