# erotic
[](https://npmjs.org/package/erotic)
`erotic` is a Node.js package to capture asynchronous errors as if they occurred synchronously, which aims at keeping the error stack readable and developer-friendly.
```
yarn add -E erotic
```
## Table of Contents
- [Table of Contents](#table-of-contents)
- [Quick Examples](#quick-examples)
* [Node.js: Reading A File](#nodejs-reading-a-file)
* [`erotic`: Standard Mode](#erotic-standard-mode)
* [`erotic`: Transparent Mode](#erotic-transparent-mode)
- [API](#api)
- [Copyright](#copyright)
## Quick Examples
The following examples show the benefits of using `erotic`.
### Node.js: Reading A File
When reading a file with Node's `readFile` method from the `fs` package, the function will be rejected without any error stack, which can make tracing errors harder in the application.
```js
import { readFile } from 'fs'
const read = async (path) => {
await new Promise((resolve, reject) => {
readFile(path, (err, data) => {
if (err) return reject(err)
return resolve(data)
})
})
}
(async () => {
const path = 'non-existent-file.txt'
try {
await read(path)
} catch ({ stack }) {
console.log(stack)
}
})()
```
```
Error: ENOENT: no such file or directory, open 'non-existent-file.txt'
```
### `erotic`: Standard Mode
`erotic` solves the problem described in the Node example by remembering error stack at the point of where the function which through was called.
```js
const read = async (path) => {
const er = erotic()
await new Promise((resolve, reject) => {
readFile(path, (err, data) => {
if (err) {
const e = er(err)
return reject(e)
}
return resolve(data)
})
})
}
```
```
Error: ENOENT: no such file or directory, open 'non-existent-file.txt'
at ReadFileContext.readFile [as callback] (/Users/zavr/adc/erotic/example/read-file.js:10:19)
at read (/Users/zavr/adc/erotic/example/read-file.js:6:14)
at /Users/zavr/adc/erotic/example/read-file.js:22:11
at Object. (/Users/zavr/adc/erotic/example/read-file.js:26:3)
```
### `erotic`: Transparent Mode
A transparent mode can be used when it's needed to completely proxy the call to a function, and hide all underlying error stack, making the error appear to happen at the point where the throwing function was called.
```js
const read = async (path) => {
const er = erotic(true)
await new Promise((resolve, reject) => {
readFile(path, (err, data) => {
if (err) {
const e = er(err)
return reject(e)
}
return resolve(data)
})
})
}
```
```
Error: ENOENT: no such file or directory, open 'non-existent-file.txt'
at /Users/zavr/adc/erotic/example/transparent.js:23:11
at Object. (/Users/zavr/adc/erotic/example/transparent.js:27:3)
```
## API
The package exports the default [`erotic` function](#erotic).
```js
import erotic from 'erotic'
```
## Copyright
Logo: [Thornton’s Temple of Flora][2]
(c) [Art Deco][1] 2018
[1]: https://artdeco.bz
[2]: https://publicdomainreview.org/2015/03/11/sex-and-science-in-robert-thorntons-temple-of-flora/