Object.prototype.toString is a thing, so how about toArray?

toArray.js

function toArray() {
  var length = this.length;
  if (
    typeof length === "number"
    && length === length
    && length > 0
  ) {
    var array = new Array(length);
    for (var i = 0; i < length; i++) {
      array[i] = this[i];
    }
    return array;
  }
  return [];
}
Object.prototype.toArray = toArray;