set-from-path

JS library to help you set values in nested objects using a string '.' separated path indicating the different keys to be accessed along the way.

It also exports a get function to get properties with the same notation

Examples

// Defaults to throwing when intermediate paths are not valid
// (non-existent or primitives)

var set = require('set-from-path').set

var a = {}
set('b', 1, a)            //> { b: 1 }
set('c', {}, a)           //> { b: 1, c: {} }
set('c.a', 1, a)          //> { b: 1, c: { a: 1 } }
set('c.b', [], a)         //> { b: 1, c: { a: 1, b: [] } }
set('c.b.0', 1, a)        //> { b: 1, c: { a: 1, b: [ 1 ] } }
set('c.b.1', { d: 1 }, a) //> { b: 1, c: { a: 1, b: [ 1, { d: 1 } ] } }
set('c.b.1.d', 2, a)      //> { b: 1, c: { a: 1, b: [ 1, { d: 2 } ] } }

set('b.c', 1, a)          //> Error: Couldn't set b.c in {"b":1,"c":{"a" ...
set('a.c', 1, a)          //> Error: Couldn't set a.c in {"b":1,"c":{"a" ...

// Also exports a setp that creates intermediate non existing paths as objects
// Similar in spirit to mkdir and mkdirp

var setp = require('set-from-path').setp
var b = { b: 1, c: { d: 2 } };
setp('c.d.a', 1, b);    //> { b: 1, c: { d: { a: 1 } } }
var c = { a: { a: 1} };
setp('b.c', 1, c);      //> { a: { a: 1 }, b: { c: 1 } }
setp('a.c.d', 1, c);    //> { a: { a: 1, c: { d: 1 } }, b: { c: 1 } }

// You get the idea...

// There is also a get function that works the same way

var get = require('set-from-path').get

var a = { b: 1, c: { d: 2, e: [3, {f: 5}, 2] } };

get('a', a)       //> undefined
get('b', a)       //> 1
get('c.a', a)     //> undefined
get('c.d', a)     //> 2
get('c.e.0', a)   //> 3
get('c.e.1', a)   //> {f:5}
get('c.e.1.f', a) //> 5

Usage

npm install --save set-from-path

Upgrade

1.0 to 2.0

All functions are exported from the module as methods. Before, the exports was the set function, but in 2.0 exports is just an object with the functions on it, so:

Change in your code:

** 1.0 **

var set = require('set-from-path')

** 2.0 **

var set = require('set-from-path').set

The rest remains the same (.setp or .set).

get was added to 2.0.