9.2 KiB
group-array
Group array of objects into lists.
Table of Contents
(TOC generated by verb using markdown-toc)
Install
Install with npm:
$ npm install --save group-array
Usage
var groupArray = require('group-array');
Examples
var arr = [
{tag: 'one', content: 'A'},
{tag: 'one', content: 'B'},
{tag: 'two', content: 'C'},
{tag: 'two', content: 'D'},
{tag: 'three', content: 'E'},
{tag: 'three', content: 'F'}
];
// group by the `tag` property
groupArray(arr, 'tag');
results in:
{
one: [
{tag: 'one', content: 'A'},
{tag: 'one', content: 'B'}
],
two: [
{tag: 'two', content: 'C'},
{tag: 'two', content: 'D'}
],
three: [
{tag: 'three', content: 'E'},
{tag: 'three', content: 'F'}
]
}
Group by multiple, deeply nested properties
// given an array of object, like blog posts...
var arr = [
{ data: { year: '2016', tag: 'one', month: 'jan', day: '01'}, content: '...'},
{ data: { year: '2016', tag: 'one', month: 'jan', day: '01'}, content: '...'},
{ data: { year: '2016', tag: 'one', month: 'jan', day: '02'}, content: '...'},
{ data: { year: '2016', tag: 'one', month: 'jan', day: '02'}, content: '...'},
{ data: { year: '2016', tag: 'one', month: 'feb', day: '10'}, content: '...'},
{ data: { year: '2016', tag: 'one', month: 'feb', day: '10'}, content: '...'},
{ data: { year: '2016', tag: 'one', month: 'feb', day: '12'}, content: '...'},
{ data: { year: '2016', tag: 'one', month: 'feb', day: '12'}, content: '...'},
{ data: { year: '2016', tag: 'two', month: 'jan', day: '14'}, content: '...'},
{ data: { year: '2016', tag: 'two', month: 'jan', day: '14'}, content: '...'},
{ data: { year: '2016', tag: 'two', month: 'jan', day: '16'}, content: '...'},
{ data: { year: '2016', tag: 'two', month: 'jan', day: '16'}, content: '...'},
{ data: { year: '2016', tag: 'two', month: 'feb', day: '18'}, content: '...'},
{ data: { year: '2017', tag: 'two', month: 'feb', day: '18'}, content: '...'},
{ data: { year: '2017', tag: 'two', month: 'feb', day: '10'}, content: '...'},
{ data: { year: '2017', tag: 'two', month: 'feb', day: '10'}, content: '...'},
{ data: { year: '2017', tag: 'three', month: 'jan', day: '01'}, content: '...'},
{ data: { year: '2017', tag: 'three', month: 'jan', day: '01'}, content: '...'},
{ data: { year: '2017', tag: 'three', month: 'jan', day: '02'}, content: '...'},
{ data: { year: '2017', tag: 'three', month: 'jan', day: '02'}, content: '...'},
{ data: { year: '2017', tag: 'three', month: 'feb', day: '01'}, content: '...'},
{ data: { year: '2017', tag: 'three', month: 'feb', day: '01'}, content: '...'},
{ data: { year: '2017', tag: 'three', month: 'feb', day: '02'}, content: '...'},
{ data: { year: '2017', tag: 'three', month: 'feb', day: '02'}, content: '...'}
]
Pass a list or array of properties:
groupArray(arr, 'data.year', 'data.tag', 'data.month', 'data.day');
Results in something like this: (abbreviated)
{ '2016':
{ one:
{ jan:
{ '01':
[ { data: { year: '2016', tag: 'one', month: 'jan', day: '01' },
content: '...' },
{ data: { year: '2016', tag: 'one', month: 'jan', day: '01' },
content: '...' } ],
'02':
[ { data: { year: '2016', tag: 'one', month: 'jan', day: '02' },
content: '...' },
{ data: { year: '2016', tag: 'one', month: 'jan', day: '02' },
content: '...' } ] },
feb:
{ '10':
[ { data: { year: '2016', tag: 'one', month: 'feb', day: '10' },
content: '...' },
{ data: { year: '2016', tag: 'one', month: 'feb', day: '10' },
content: '...' } ],
'12':
[ { data: { year: '2016', tag: 'one', month: 'feb', day: '12' },
content: '...' },
{ data: { year: '2016', tag: 'one', month: 'feb', day: '12' },
content: '...' } ] } },
two:
{ jan:
{ '14':
[ { data: { year: '2016', tag: 'two', month: 'jan', day: '14' },
content: '...' },
{ data: { year: '2016', tag: 'two', month: 'jan', day: '14' },
content: '...' } ],
'16':
[ { data: { year: '2016', tag: 'two', month: 'jan', day: '16' },
content: '...' },
{ data: { year: '2016', tag: 'two', month: 'jan', day: '16' },
content: '...' } ] },
feb:
{ '18':
[ { data: { year: '2016', tag: 'two', month: 'feb', day: '18' },
content: '...' } ] } } },
'2017':
{ two:
{ feb:
{ '10':
[ { data: { year: '2017', tag: 'two', month: 'feb', day: '10' },
content: '...' },
{ data: { year: '2017', tag: 'two', month: 'feb', day: '10' },
content: '...' } ],
'18':
[ { data: { year: '2017', tag: 'two', month: 'feb', day: '18' },
content: '...' } ] } },
three:
{ jan:
{ '01':
[ { data: { year: '2017', tag: 'three', month: 'jan', day: '01' },
content: '...' },
{ data: { year: '2017', tag: 'three', month: 'jan', day: '01' },
content: '...' } ],
'02':
[ { data: { year: '2017', tag: 'three', month: 'jan', day: '02' },
content: '...' },
{ data: { year: '2017', tag: 'three', month: 'jan', day: '02' },
content: '...' } ] },
feb:
{ '01':
[ { data: { year: '2017', tag: 'three', month: 'feb', day: '01' },
content: '...' },
{ data: { year: '2017', tag: 'three', month: 'feb', day: '01' },
content: '...' } ],
'02':
[ { data: { year: '2017', tag: 'three', month: 'feb', day: '02' },
content: '...' },
{ data: { year: '2017', tag: 'three', month: 'feb', day: '02' },
content: '...' } ] } } } }
About
Related projects
- arr-flatten: Recursively flatten an array or arrays. This is the fastest implementation of array flatten. | homepage
- get-value: Use property paths (
a.b.c
) to get a nested value from an object. | homepage - group-object: Group object keys and values into lists. | homepage
- union-value: Set an array of unique values as the property of an object. Supports setting deeply… more | homepage
Contributing
Pull requests and stars are always welcome. For bugs and feature requests, please create an issue.
Contributors
Commits | Contributor |
---|---|
23 | doowb |
6 | jonschlinkert |
1 | cperryk |
Building docs
(This project's readme.md is generated by verb, please don't edit the readme directly. Any changes to the readme must be made in the .verb.md readme template.)
To generate the readme, run the following command:
$ npm install -g verbose/verb#dev verb-generate-readme && verb
Running tests
Running and reviewing unit tests is a great way to get familiarized with a library and its API. You can install dependencies and run tests with the following command:
$ npm install && npm test
Author
Brian Woodward
License
Copyright © 2017, Brian Woodward. Released under the MIT License.
This file was generated by verb-generate-readme, v0.4.2, on February 24, 2017.