Sharing Data Between Javascript Files

If JSON data is less than 5 mb then you can use localStorage to save the output in browser.

In first js file:

function fOne(){
    var jsonStr = ''; //insert some json data here
    localStorage.setItem("myJson", JSON.stringify(jsonStr)); //save data
}

In your second js file:

function fTwo(){
    if (localStorage.getItem("myJson") !== null) {
        var passedJson = localStorage.getItem("myJson"); //get saved data anytime
    }
}

It is hard to say without some code to reference but maybe just a global variable with a check if its null.

var myJsonString = null;

function one () {
    var jsonString = "[]";
    myJsonString = jsonString;
}

function two () {
    //string not set so bail
    if (myJsonString === null) { return; }
}

So it actually depends what environment you are programming in. If its a web browser, all of the code is in the global space actually and is run in order. so if you have <script src="file1"> then <script src="file2"> in your html file, and you put x = 10 in the first file and use it in the second, you will have no problems. If you are using node.js, I can post a solution for that as well, just let me know.

(btw if you put x = 10 in the second file and reference it from the first it will throw an error)

There are ways of avoiding this, such as using a document.ready function or wrapping things in functions and then calling them at the end. You need to make sure that functions and variables are created before being used (this is a common mistake beginners make and are confused by)