# map-indexed-xf

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This module defines a function that returns a transducer which calls a given
function with each value and its index. This transducer may be used with
Javascript transducer libraries such as
[jlongster/transducers.js](https://github.com/jlongster/transducers.js) and
[cognitect-labs/transducers-js](https://github.com/cognitect-labs/transducers-js).

## Example

```js
const t = require('transducers.js');
const mapIndexed = require('map-indexed-xf');

const result = t.toArray([5,6,7], t.compose(
  t.map(x => x*10),
  mapIndexed((x, i) => [i, x])
));

console.log(result); // [[0, 50], [1, 60], [2, 70]]
```

## Types

[TypeScript](https://www.typescriptlang.org/) type definitions for this module
are included! The type definitions won't require any configuration to use.