Possible to assign to multiple variables from an array?
Destructuring assignment was standardized in ECMAScript 2015 (a.k.a. ES6). But not all browsers have implemented destructuring yet (as of March 2016), and even when they do it will take a while before users update to a browser with support. See examples in the spec for all the awesome things you can do. Here are some:
// Assign from array elements
var [key, value] = "key:value".split(":");
// key => 'key'
// value => 'value'
// Assign from object properties
var {name: a, age: b} = {name: 'Peter', age: 5};
// a => 'Peter'
// b => 5
// Swap
[a, b] = [b, a]
// a => 5
// b => 'Peter'
Because this feature breaks backwards compatibility, you'll need to transpile the code to make it work in all browsers. Many of the existing transpilers support destructuring. Babel is a very popular transpiler. See Kangax´s table of browser and transpiler ES6-support.
More info:
Compatibility table for ES6 browser support
Exploring ES6 - Destructuring chapter
If you want to know what's coming, read the section on Destructuring Assignment.
https://developer.mozilla.org/en/New_in_javascript_1.7
What language features you can use is always dependent on your environment.
Developing for Mobile Safari (or a web stack for other browsers like the Palm Pre, Android, etc.) or AIR, for example, is more predictable than developing for the web at large (where you still have to take even IE6 into account).
A cross-browser solution to the problem at hand would be to initialize an array that had a list of the variables you want to fill in window.variable format, then just loop through. Can't imagine why you'd do it though. Seems like there would always be a better solution.
Use destructuring assignment, a feature of ES6:
var [x, y] = [1, 2];
console.log(x, y); // 1 2