eval.js

What is eval.js?

eval.js is a tiny piece of JavaScript which saves you the pain of repeatedly evaluating object (nested) properties. eval.js handles evaluation of object properties with the (dot notation) string key(s) - thus allowing quick&easy dynamic property evaluation.

How to install eval.js?

Via Bower:

bower install eval.js

Via NPM:

npm install eval.js

How to use eval.js?

In browser:

<script src="/bower_components/eval.js/eval.min.js"></script>

In NodeJs:

var evalJs = require('eval.js');

You must provide eval.js with an object

var testObject = {
    a: {},
    b: {
        bb: true
    },
    c: {
        cc: {
            ccc: false
        }
    },
    d: {
        dd: {
            ddd: {
                dddd: ''
            }
        }
    }
};

Check if given object has property

evalJs.isSet(testObject, 'a');                                          // true
evalJs.isSet(testObject, 'b.bb');                                       // true
evalJs.isSet(testObject, 'c.cc.ccc');                                   // true
evalJs.isSet(testObject, 'd.dd.ddd.dddd');                              // true
evalJs.isSet(testObject, 'z');                                          // false
evalJs.isSet(testObject, 'z.zz');                                       // false

Check if given object has multiple properties

evalJs.isSet(testObject, ['a']);                                        // true
evalJs.isSet(testObject, ['b', 'b.bb']);                                // true
evalJs.isSet(testObject, ['c', 'c.cc', 'c.cc.ccc']);                    // true
evalJs.isSet(testObject, ['d', 'd.dd', 'd.dd.ddd', 'd.dd.ddd.dddd']);   // true
evalJs.isSet(testObject, ['z']);                                        // false
evalJs.isSet(testObject, ['z', 'z.zz']);                                // false

Get the given object property value

evalJs.get(testObject, 'a');                                            // {}
evalJs.get(testObject, 'b');                                            // { bb: true }
evalJs.get(testObject, 'b.bb');                                         // true
evalJs.get(testObject, 'c.cc.ccc');                                     // false
evalJs.get(testObject, 'd.dd.ddd.dddd');                                // ''
evalJs.get(testObject, 'z.zz.zzz');                                     // undefined