fun with JS arrays
var a = [];
a[Math.pow(2, 32) - 2] = "max index"; // highest non-expando indexed property
console.log(a.length === Math.pow(2, 32) - 1); // true
try {
a.push("whoa", "EVEN MOAR WHOA");
} catch (e) {
console.log(e instanceof RangeError); // true
}
console.log(a.length === Math.pow(2, 32) - 1); // true
console.log(a[Math.pow(2, 32) - 1] === "whoa"); // true
console.log(a[Math.pow(2, 32)] === "EVEN MOAR WHOA"); // true