How do you find out the caller function in JavaScript?

Question

function main()
{
   Hello();
}

function Hello()
{
  // How do you find out the caller function is 'main'?
}

Is there a way to find out the call stack?

Answer 1

function Hello()
{
    alert("caller is " + Hello.caller);
}

Note that this feature is non-standard, from Function.caller:

Non-standard
This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.

---

The following is the old answer from 2008, which is no longer supported in modern Javascript:

function Hello()
{
    alert("caller is " + arguments.callee.caller.toString());
}