how to wait with setTimeout until a variable get loaded and, at the same time, receive HTTP requests!

Question

I\' ve made a in JavaScript function to check every 100 ms if a global variable is loaded. When the variable will be loaded the function will return the value of the variable as

Answer 1

I would probably make the remaining arithmetric operations a callback. Something like:

function checkVariable()
{
    if ( myvar != null )
    {
            computeVariable(myVar);
    }
    else
    {
            window.setTimeout("checkVariable();",100);
    }
} 

Then:

// arithmetis operations... [1]

myVar = checkVariable();

function computeVariable(myVar) {
  // arithmetic operations that use myVar [2]
}