Javascript can't access array from one file to another

Question

In my php page, i'm including 2 .js files, and the first one creates and populates a js array which I need to access in the second .js file. For some reason, I'm getting an error that the array is undefined when I know for a fact that it's being populated. Why is this broken?
What am I doing wrong?

Error: ReferenceError: sl is not defined

first.js

var sl = [];
for (var i = 0; i < j.length; i++) {
    options += '<option value="' + j[i].value + '">' + j[i].text + '</option>';
    sl[j[i].value] = [];
    sl[j[i].value]['shopping_list'] = j[i].text;
    sl[j[i].value]['is_private']= j[i].is_private;
    console.log('printing SL for ' + j[i].value);
    console.log(sl[j[i].value]['shopping_list']);
}

second.js

$("#shopping_list_name").val(sl[$("#existing_shopping_lists").val()]['shopping_list']);

Answer 1

Is the code that you cited from first.js inside a function (possibly a $(function() {}); )? JavaScript has functional scoping making the var sl=[] not global (regardless of order)