Here are some helper functions I use:
Array.contains = function (arr, key) {
for (var i = arr.length; i--;) {
if (arr[i] === key) return true;
}
return false;
};
Array.add = function (arr, key, value) {
for (var i = arr.length; i--;) {
if (arr[i] === key) return arr[key] = value;
}
this.push(key);
};
Array.remove = function (arr, key) {
for (var i = arr.length; i--;) {
if (arr[i] === key) return arr.splice(i, 1);
}
};