Skip to content

sindresorhus/map-obj

main
Switch branches/tags

Name already in use

A tag already exists with the provided branch name. Many Git commands accept both tag and branch names, so creating this branch may cause unexpected behavior. Are you sure you want to create this branch?
Code

Latest commit

 

Git stats

Files

Permalink
Failed to load latest commit information.
Type
Name
Latest commit message
Commit time
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

map-obj

Map object keys and values into a new object

Install

npm install map-obj

Usage

import mapObject, {mapObjectSkip} from 'map-obj';

const newObject = mapObject({foo: 'bar'}, (key, value) => [value, key]);
//=> {bar: 'foo'}

const newObject = mapObject({FOO: true, bAr: {bAz: true}}, (key, value) => [key.toLowerCase(), value]);
//=> {foo: true, bar: {bAz: true}}

const newObject = mapObject({FOO: true, bAr: {bAz: true}}, (key, value) => [key.toLowerCase(), value], {deep: true});
//=> {foo: true, bar: {baz: true}}

const newObject = mapObject({one: 1, two: 2}, (key, value) => value === 1 ? [key, value] : mapObjectSkip);
//=> {one: 1}

API

mapObject(source, mapper, options?)

source

Type: object

The source object to copy properties from.

mapper

Type: (sourceKey, sourceValue, source) => [targetKey, targetValue, mapperOptions?] | mapObjectSkip

A mapping function.

mapperOptions

Type: object

shouldRecurse

Type: boolean
Default: true

Whether targetValue should be recursed.

Requires deep: true.

options

Type: object

deep

Type: boolean
Default: false

Recurse nested objects and objects in arrays.

target

Type: object
Default: {}

The target object to map properties on to.

mapObjectSkip

Return this value from a mapper function to exclude the key from the new object.

import mapObject, {mapObjectSkip} from 'map-obj';

const object = {one: 1, two: 2}
const mapper = (key, value) => value === 1 ? [key, value] : mapObjectSkip
const result = mapObject(object, mapper);

console.log(result);
//=> {one: 1}

Related

  • filter-obj - Filter object keys and values into a new object

Get professional support for this package with a Tidelift subscription
Tidelift helps make open source sustainable for maintainers while giving companies
assurances about security, maintenance, and licensing for their dependencies.