ReferenceError: localStorage is not defined - requireJS, r.js optimizer and localStorage

Question

I'm trying to optimize my requireJS JavaScript app with r.js. Unfortunately it stops when it rans over the function "localStorage" (the browser-builtin localStorage-function).

The error message:

ReferenceError: localStorage is not defined

The function where the error occures:

function getFromLocalStorage()
{
    return localStorage.getItem('foo') ? JSON.parse(localStorage.getItem('foo')) : {};
}

How to fix this kind of error? Is is possible to use localStore within the r.js optimizer?

More information:

The build script:

({
    appDir: "../",
    baseUrl: "js/",
    dir: "./build",
    mainConfigFile: "app.js",
    paths: {
        jQuery: "empty:"
    },
    name: "app",
    findNestesDependencies: true
})

Application structure:

/
---> /js (where app.js lies)
     ---> /app (here lies the file with the localStore-call)
     ---> /lib

Solution

First off, you have a typo in your code above.

I didn't want to just edit your code, but I assume that:

 return localStorage.getItemfootv') ? JSON.parse(localStorage.getItem('foo')) : {};

Is supposed to be:

return localStorage.getItem('foo') ? JSON.parse(localStorage.getItem('foo')) : {};

With that change, I copied your code into a project of mine and it ran through the optimizer just fine. What version are you using? I tried with the latest version, 2.1.1.

If it's not an issue with the optimizer version you're using, I would try changing references of localStorage to window.localStorage and see if that make a difference.

Comments

[akluth]

Thank you, this was just a typo, this typo wasn't in the original code. I'm using version 2.1.1 either and tried to use window.localStorage - unsuccessfully, now 'window' is not defined.

[Waxen]

I'm not sure exactly what to make of that, but that at least indicates that it's not a problem with using localStorage, but rather with the optimization process. Some quick googling turned up this: groups.google.com/forum/?fromgroups=#!msg/requirejs/Zt9FOu74‌​NqA/…. Check the command you're invoking the optimizer with and make sure it's correct.