As an enhancement, add a third parameter to inArray that is a callback function for a custom equality comparison. This would allow for the matching of custom objects within an array without having to have a reference to the original object. For example, you could find a Date within an array like this:

var d1 = new Date(2010, 1-1, 1);

var d2 = new Date(2010, 2-1, 1);

var d3 = new Date(2010, 1-1, 1);

var dates = [d1, d2];

var index = $.inArray(d3, dates, function(a, b) {

return a.getTime() == b.getTime();

});

Maybe there could even be common comparators built-in, such as the date one above.

$.comparator.date = function(a, b) {

return a.getTime() == b.getTime();

};