https://github.com/sindresorhus/map-obj
Map object keys and values into a new object
https://github.com/sindresorhus/map-obj
Last synced: 12 months ago
JSON representation
Map object keys and values into a new object
- Host: GitHub
- URL: https://github.com/sindresorhus/map-obj
- Owner: sindresorhus
- License: mit
- Created: 2014-10-12T11:42:51.000Z (over 11 years ago)
- Default Branch: main
- Last Pushed: 2023-10-16T18:47:08.000Z (over 2 years ago)
- Last Synced: 2025-04-14T07:22:03.283Z (about 1 year ago)
- Language: JavaScript
- Size: 35.2 KB
- Stars: 212
- Watchers: 5
- Forks: 42
- Open Issues: 4
-
Metadata Files:
- Readme: readme.md
- Funding: .github/funding.yml
- License: license
- Security: .github/security.md
Awesome Lists containing this project
- fucking-awesome-micro-npm-packages - map-obj - Map object keys and values into a new object. (Modules / Object)
- awesome-micro-npm-packages - map-obj - Map object keys and values into a new object. (Modules / Object)
- awesome-micro-npm-packages-zh - map-obj
- awesome-micro-npm-packages - map-obj - Map object keys and values into a new object. (Modules / Object)
README
# map-obj
> Map object keys and values into a new object
## Install
```sh
npm install map-obj
```
## Usage
```js
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.
```js
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](https://github.com/sindresorhus/filter-obj) - Filter object keys and values into a new object
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