how can I access a variable which is passed from controller to view in helper function?

I have one view which is calling one helper function and in that function, I want to access the variable which is passed in the view from controller I tried use statemen but still, I am getting an error of undefined variable here is my code.

return view('myview')->with([
            'myvariablename'     => true, ]);

below is code in my view file

@if(myHelperFunction()){
 // do stuff
}

here is my code in helper function where I want to use that variable which is passed from controller to view.

function myHelperFunction()
{

    if (isset($myvariablename) && $myvariablename) {
        return true;
    }
    return false;
}

via Chebli Mohamed