error passing can.Observe.List to custom Mustache element helper

[rwaldin]

I'm trying to pass a can.Observe.List to a custom Mustache element helper as a parameter and I get this error:

[can.zepto:3590] TypeError: 'undefined' is not a function (evaluating '(newVal || "").replace(/['"]/g, '')')

Here's a demonstration of the problem: http://jsfiddle.net/rwaldin/qc3XZ/

Uncomment the helper in the first list item to see the problem.

[demyanrogozhin]

Sorry for bumping old issue, but I faced same error.
And that's what I wound:

First of all - generated template is wrong - no can.view.pending() called after adding first tag.
I added work around: http://jsfiddle.net/qc3XZ/6/

Second - for Observable data types (data.isListening is true) helper return value added on mustache stack, which result invalid HTML :

  < li function(el) { if //..and so on }  data-view-id='2'> observeList broken < /li > "

Third - compete-function can return function, but do not call OR even check value is not valid object.

My summary:
Using helper that return function for observable objects is bad idea.

[azazel75]

i really don't know what the previous commenter means with "- no can.view.pending() called after adding first tag" but i've used a can.zepto.js compiled with sources containing my patch for bug #463 and it seems to work, check it out: http://jsfiddle.net/qc3XZ/9/

[daffl]

Thanks for the update! I will check the fix and hopefully manage to write tests for all the issues. Lets hope it works for all cases :)