an attempt at javascript continuation passing style conversion from scheme

cps.js

function cps_prim(f) {
  return function() {
    var r = arguments.reverse();
    return r[0]( f.apply(this, arguments.slice(1).reverse()) );
  }
}

function _sqrt() { return cps_prim(function(x) { return 6; }); }

function _mul(a, b) { return a*b; }
function mul() { return cps_prim(_mul); }

function pyth(x, y, k) {
  return mul(x, x, function(x2) {
              return mul(y, y, function(y2) {
                return mul(x2, y2, function(x2py2) {
                  return _sqrt(x2py2, k); });
              });
            });
}

console.log("begin");
pyth(20, 50, function(r) { console.log("r: "); console.log(r); });
console.log("end");