# deferinfer

> Alternative converter between promises and callbacks

Latest version **1.0.1** (published 2019-08-28) · MIT license · 0 weekly downloads

## Install

```sh
npm install deferinfer
pnpm add deferinfer
yarn add deferinfer
bun add deferinfer
```

## Health

**Score 15/100 (F)** — status: abandoned.

Positive: no vulnerabilities.

Warnings: low downloads; no types; no esm support.

Negative: abandoned; low maintenance score.

## Facts

| | |
|---|---|
| Version | 1.0.1 |
| Published | 2019-08-28 |
| First published | 2019-08-28 |
| Weekly downloads | 0 |
| License | MIT |
| TypeScript types | none |
| Module format | CommonJS |
| Dependencies | 0 |
| Unpacked size | 3.7 KB |
| Known vulnerabilities | 0 |
| Install scripts | no |
| GitHub stars | 1 |
| Author | Tony Ivanov |
| Maintainers | telamon |
| Keywords | defer, infer, promisify, callbackify, promise, callback |

## Links

- npm: https://www.npmjs.com/package/deferinfer
- Repository: https://github.com/telamon/deferinfer
- Homepage: https://github.com/telamon/deferinfer#readme
- Issues: https://github.com/telamon/deferinfer/issues
- npm.io page: https://npm.io/package/deferinfer

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## Recent versions

- 1.0.1 (latest) — 2019-08-28

## README

# deferinfer

> Alternative converter between promises and callbacks

### installation

```bash
npm install deferinfer

# -- or --

yarn add deferinfer
```

```js
const { defer, infer } = require('promise-util')

// -- or --

const defer = require('promise-util').defer
```

## `defer(callback)` -> `Promise`

Convert callback function into to promise

```js
const result = await defer(done => someCallbackFunction(done))
```

Properly forwards error

```js
defer(done => {
  done(new Error()) // forwarded to .catch()
  throw new Error() // forwarded to .catch()
  done(null, 42)    // forwarded to .then()
})
  .then(console.log)
  .catch(console.error)
```

Async method support

```js
defer(async done => {
  const result = await anotherPromise()
  done(null, result)promise-util
})
```

## `infer(promise, callback)` -> `Promise`

Convert promise to callback

```js
const p = infer(Promise.resolve(42), (err, res) => {
  if (err) console.error(err)
  else console.log(res)
})
```

Define promise/callback agnostic functions

```js
function add(a, b, callback) {
  const promise = defer(done => {
    done(null, a + b)
  })
  return infer(promise, callback)
}

add(5, 7, (err, sum) => {
  console.log(sum) // => 12
})

const sum = await add(6, 4)
console.log(sum) // => 10
```

---
_Source: https://npm.io/package/deferinfer · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._