es6 proxy profile method example

profile-proxy.js

function profile (o) {
  for (var key in o) {
    var field = o[key];
    if (typeof field == 'function') {
      o[key] = Proxy.createFunction({},
        // call
        function () {
          var before = new Date;
          var res = field.apply(o, arguments);
          var spent = new Date - before;
          console.log('time spent calling "%s": %sms', key, spent);
          return res;
        },
        // new
        function () {
        });
    }
  }
}

var o = {
  doit: function () {
    var i = 100000000;
    while (i--);
    return 42;
  }
}

profile(o);
console.log(o.doit());