Coffeescript if variable is undefined in function

Question

Is there a way to force Coffeescript to always convert

if x?
  console.log "hello"

to

 if (typeof x !== "undefined" && x !== null) {
  console.log("hello");
}

The reason I'm asking is because if we have the following:

x = "hello"

if x?
  console.log "hello"

It gets converted to:

var x;

x = "hello";

if (x != null) {
  console.log("hello");
}

While this is not a problem in the code above, it is problematic in functions to which an undefined variable is passed.

Answer 1

x != null also covers x != undefined so the converted code should not be entering the if statement if x is undefined.

See more in this answer