I'm rendering a similar block of HTML for several slightly different objects. They're 90% the same, but each one has some specific quirks that demand extra observables. I would like to render each of these mostly-similar items in a template block, but I'm running into problems with undefined objects.

Basically, I want to check for the existence of an observable object before rendering it in the template.

I am trying to do something like this:

<div data-bind=foreach: blocks>

<h2 data-bind=text: normalHeader><h2>

<p data-bind=text: normalText></p>

<!-- ko if: specialText --><p data-bind=text: specialText></p><!-- /ko -->

</div>

So if specialText doesn't exist (not just has no value, but doesn't exist at all) for that iteration of blocks, ignore the conditional. The error I'm getting is:

Uncaught Error: Unable to parse bindings.

Message: ReferenceError: specialText is not defined;

From what I understand of Knockout's if binding, it should work if the object returns any kind of false-like value, like null or undefined, which means that the if binding should gracefully fail, which it definitely isn't.

Is there any way to make this work?