How do I use the CoffeeScript existential operator to check some object properties for undefined?

Question

I would like to use the CoffeeScript existential operator to check some object properties for undefined. However, I encountered a little problem.

Code like this:

Answer 1

Wild guess; have you tried console.log test.test if test?.test??

Just tested it with coffee -p -e 'console.log test.test if test?.test?', which compiles to:

(function() {

if ((typeof test !== "undefined" && test !== null ? test.test : void 0) != null) { console.log(test.test); }

}).call(this);