Question

Are global variables accessible in jquery nested functions?
Im having an issue that i cant solve. One object property changes and another one doesn’t

The situtation is this

    for(var key in object) {
        if(object[key].boolean) {
            alert(object[key].value)
            $.get(url, "data", function(data) {
                if(parseInt(data) > object[key].int) {
                    alert(object[key].value);
                    object.int = data;
                }
            });
        }
    }

The issue i am having is the object[key].value does not hold its value. Both alerts have different values so i cant use it in the nested return function. Also object[key].int gets updated correctly which is more confusing. Object is declared as a global variable.

Any suggestions is greatly appreciated.

Answer 1

your anonymous wrapper is called only after get becomes success,it is not called right away, looks like some situation like

Return a function from the anonymous wrapper?

are you getting the last item alerted from the inside closure?

var object = {
    x:10,
    y:20,
    z:30
};
for(var key in object) {
            console.log("outside closure",object[key]);
                $.get("/echo/html?data=asdf" ,(function(keyAlias) {
                    return function(data) {
                        console.log("inside closure",object[keyAlias],data);
                        //your logis goes here
                    }
                 })(key));
    }

Fiddle : http://jsfiddle.net/eTdv5/1/ (check console logs)

Explaining the whole thing is not becessary as I guess, you can check the above mentioned SO post, In case of anything unclear please ask.

Explanation:

First, key = 10

$.get("/echo/html?data=asdf" , <at this place key is 10> );

(function(key) {})(key) is like calling display(key), think that you are writing display function right away and calling it with an argument key.

return function(data) {}; will return a function, in effect think like (function(key) {})(key) getting replaced with this returned function.

That will give you an introduction, now how the scope is managed:

The key will change its value as the for in loop loops through object, but each callback function we created has its own keyAlias assosiated with it which corresponds to the value of key at the time callback function was crated using (function(key) {})(key)