Dynamically access object property using variable

I'm trying to access a property of an object using a dynamic name. Is this possible?

const something = { bar: "Foobar!" };
const foo = 'bar';
something.foo; // The idea is to access something.bar, getting "Foobar!"

---

There are two ways to access properties of an object:

Dot notation: something.bar

Bracket notation: something['bar']

The value between the brackets can be any expression. Therefore, if the property name is stored in a variable, you have to use bracket notation:

var foo = 'bar';
something[foo];
// both x = something[foo] and something[foo] = x work as expected

---

This is my solution:

function resolve(path, obj) {
    return path.split('.').reduce(function(prev, curr) {
        return prev ? prev[curr] : null
    }, obj || self)
}

Usage examples:

resolve("document.body.style.width")
// or
resolve("style.width", document.body)
// or even use array indexes
// (someObject has been defined in the question)
resolve("part.0.size", someObject) 
// returns null when intermediate properties are not defined:
resolve('properties.that.do.not.exist', {hello:'world'})

---

In javascript we can access with:

dot notation - foo.bar

square brackets - foo[someVar] or foo["string"]

But only second case allows to access properties dynamically:

var foo = { pName1 : 1, pName2 : [1, {foo : bar }, 3] , ...}

var name = "pName"
var num  = 1;

foo[name + num]; // 1

// -- 

var a = 2;
var b = 1;
var c = "foo";

foo[name + a][b][c]; // bar

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