Acme.BookStore.HttpApi.Host/node_modules/bach/README.md

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# bach

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Compose your async functions with elegance.

## Usage

With `bach`, it is very easy to compose async functions to run in series or parallel.

```js
var bach = require('bach');

function fn1(cb) {
  cb(null, 1);
}

function fn2(cb) {
  cb(null, 2);
}

function fn3(cb) {
  cb(null, 3);
}

var seriesFn = bach.series(fn1, fn2, fn3);
// fn1, fn2, and fn3 will be run in series
seriesFn(function(err, res) {
  if (err) { // in this example, err is undefined
    // handle error
  }
  // handle results
  // in this example, res is [1, 2, 3]
});

var parallelFn = bach.parallel(fn1, fn2, fn3);
// fn1, fn2, and fn3 will be run in parallel
parallelFn(function(err, res) {
  if (err) { // in this example, err is undefined
    // handle error
  }
  // handle results
  // in this example, res is [1, 2, 3]
});
```

Since the composer functions return a function, you can combine them.

```js
var combinedFn = bach.series(fn1, bach.parallel(fn2, fn3));
// fn1 will be executed before fn2 and fn3 are run in parallel
combinedFn(function(err, res) {
  if (err) { // in this example, err is undefined
    // handle error