knockout bindingHandler doesn't work: Why?

Question

I`m creating a binding with knockout...see the code

ko.bindingHandlers.fadeVisible = {
  init: function(element, valueAccessor) {
    // Start visible/invisible according to initial value

    var shouldDisplay = valueAccessor();
    $(element).toggle(shouldDisplay);

    // Handle mouse events on the stars
  },

  update: function(element, valueAccessor) {
    // On update, fade in/out
    var shouldDisplay = valueAccessor();

    shouldDisplay ? $(element).fadeIn() : $(element).fadeOut();

  } 
};

... something seems to be wrong with the fadeOut() function on the last line: the Editor alerts:

"expected an assignment or function call and instead saw expression"

I´ve no idea why, since fadeOut() is obviously a function...

Answer 1

Try using

ko.unwrap(shouldDisplay)

on each of your shouldDisplay variables.

Answer 2

The message is from JSLint/JSHist and you can ignore it.

See http://jslinterrors.com/expected-an-assignment-or-function-call