# object-fields

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Utility functions around object paths

## Install

    $ npm i --save object-fields

## Usage

<!-- eslint-disable import/no-unresolved, import/no-extraneous-dependencies -->
```js
import {
  split, join, getParents, Retainer
} from 'object-fields';

split('data(file1,file2)');
// => ["data.file1", "data.file2"]
join(['data', 'data']);
// => "data"
join(['path.to.thing', 'path.to.other.thing']);
// => "path.to(thing,other.thing)"
getParents(['child', 'parent.child', 'grandparent.parent.child']);
// => ['parent', 'grandparent', 'grandparent.parent']

const data = [{ id: 1, name: 'one' }, { id: 2, name: 'two' }];
const retain = Retainer(['name']);
retain(data); // updates data in place
// data => [{ name: 'one' }, { name: 'two' }]
```

## Methods

### split

Takes a shortened input string and separates it into an array.

### join

Takes array of selectors and shortens it into a string

### getParents

Takes array of selectors and returns unique, true parents.

### Retainer

Takes array of selectors and returns retain function. The retain function takes an object and removes non selected fields it.

## Known Limitations

This package does not currently support escaping.