underscore-keypath

key-path mechanism extensions for underscore (mixin).

underscore-keypath let you access JavaScript objects and arrays with keypath easily.

var foo = {
  bar : {
    name : "Cool!"
  },
  scores : [55, 27, 100, 33]
};
 
_(foo).valueForKeyPath("bar.name");           // --> "Cool!"
_(foo).setValueForKeyPath("bar.name", "BAR"); // --> sets foo.bar.name as "BAR"
_(foo).valueForKeyPath("scores.@max");        // --> 100

Install

NodeJS

$ npm install underscore-keypath

var _ = require("underscore-keypath");

or you may want to use origianl underscore:

var _ = require("underscore");
require("underscore-keypath"); // it will extend original underscore

in this case, please install "underscore" first.

$ npm install underscore
$ npm install underscore-keypath

Otherwise, underscore-keypath extends separated underscore in sandbox.

Meteor

$ meteor add jeeeyul:underscore-keypath

Front-end

$ bower install underscore-keypath

Or just download underscore-keypath.js manually.

Examples

var list = [{
  name : "foo",
  info : {
    favoriteColor : "red",
    age : 20
  }
},{
  name : "bar",
  info : {
    favoriteColor : "green",
    age : 17
  }
},{
  name : "zar",
  info : {
    favoriteColor : "red",
    age : 34
  }
}];
 
_(list).pluckByKeyPath("info.age");           // --> [20, 17, 34]
_(list).sortByKeyPath("info.age");            // --> [{name:"bar", ..}, {name:"foo", ..}, {name:"zar", ..}]
_(list).groupByKeyPath("info.favoriteColor"); // --> {red:2, green:1}
 

See API Document