findItem.js

var findItem = function(jid, items){
    for(var i = 0; i < items.length; ++i){
        var item = items[i];
        if(item.jid === jid){
            return item;
        }
    }
    return null;
}

findItem_some.js

var findItem = function(jid, items){
    var foundItem = null;
    dojo.some(items, function(item){
        return (item.jid === jid) ? (foundItem = item, true) : false;
    });
    return foundItem;
}

Haha, you've just implemented Common Lisp's some; I was wondering if there was a more concise solution apart from writing some in JS. If Javascript's Array.some behaved like this rather than returning just a boolean, it would have been so much more useful.

oh, yeah some is pretty neat in that it returns the value. I like that. Ruby's array.find does this, that's why I called it find. There is also an "any" which is meant to be used like some. Except you can rely on it even if your array contains false or nil ;-)