Michael Best

That's an interesting idea, but it could be done today by returning a computed. ``` ko.filters.phone = function (value) { return ko.pureComputed({ read: function () { return (ko.unwrap(value) || '').replace(/(\d{3})(\d{3})(\d{4})/,...

I didn't actually test it, so let me know if you run into any problems. This actually isn't best practice in terms of performance because the computed will be re-created...

Try using `allowBindings` as described in the [Knockout docs](http://knockoutjs.com/documentation/custom-bindings-controlling-descendant-bindings.html).

Have you tried ``?

No problem. I could make it more clear in the documentation.

Sorry for taking so long to reply. I think it's a good idea to include examples, but I haven't yet had the time to do it.

Perhaps it could be built in, but you can always pass the element to the filter: `text: field | filter:$element`

If this would support 3.4.0, it would have to override the native deferred updates.

I was certainly hoping that I wouldn't have to.

Can you tell me more about your application and what steps you went through to produce the error?