getting variable value from inside a callback function

Question

I am trying to pull a variable's value from a callback function. What am I doing wrong here?

var storyList = [];
var storyTemp ={};

// get list of all stories
db.getAllStoriesSet(function(err, reply) {
    if (err) throw err;
    else {
        storyList = reply;
        console.log("storylist inner: " + storyList);
    };
});
console.log("storylist outer: " + storyList);

in the above code, I am expecting the inner and outer storylist values to be same. however the outer storyList value still comes as a null list.

EDIT: to add to the question. I have initialized a variable storyList outside the async function. i am then taking the reply from the async function and putting it in the variable storyList. I was hoping to cheat my way out of the async pit of slow and brutal death that I have apparently dug for myself. shouldnt it have worked?

Denys Séguret · Accepted Answer · 2013-01-23 20:39:51Z

5

If getAllStoriesSet is asynchronous, then the line following its call is called before the callback is executed. So storyList is just like it was before the call.

That's the reason why you provide a callback : you must put inside the callback the code which needs the value of reply.

answered Jan 23, 2013 at 20:39

Denys Séguret

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1 Comment

Rishav Sharan Over a year ago

it is an async function. How can i get the value of stoyList without a callback? This whole async programming is making my life hell. :/ do i need to add another callback? The way I am daisy-chaining my async functions and callbacks, I might as well do synchronous programming.

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