attr.coffee

for own attr, value of this
  if attr == 'foo' && value == 'bar'
    console.log 'Found a foobar!'

attr.js

var attr, value;
var __hasProp = Object.prototype.hasOwnProperty;
for (attr in this) {
  if (!__hasProp.call(this, attr)) continue;
  value = this[attr];
  if (attr === 'foo' && value === 'bar') {
    console.log('Found a foobar!');
  }
}