Using throw.js, show how to tail-call optimize a recursive function using ...exceptions?!

tco.js

var throwup = require('throw').throwup, makecallable = require('throw').makecallable;

var recurse = throwup(_recurse);
var callable_recurse = makecallable(_recurse);
var result = callable_recurse(parseInt(process.argv[2], 10) || 5000, 0);
console.log('found', result);

function _recurse(n, j) {
    if(n>0) return recurse(n-1, j+1);
    else return j;
}