Ok foud a workaround.

In my case I wanted to check if one ore more products belongs to a group. If the condiditon was true a div containig table and data is visible, if not its hidden. So I made something like this:

<div t-if=" True in [z.product_id.categ_id.name == 'WiMax' for z in o.order_line]" >...(your content goes here ).</div>

You can make inline labda function to loop over "o.order_line" and chek if "o.order_line.product_id.categ_id.name" (this is the category name) of each line is the category name you are looking for. This will result in list ex. [False, False, False, False, True]. So "True in [...]" evaluates if there is True in the list.  Hope you can use the same logic in your problem.

Thanks for that. But this bug seems to defeat a major purpose of the loop function in Qweb.

Hello,

A discussion exits on github, you can check here https://github.com/odoo/odoo/issues/4461#issuecomment-72199618 the explication of Odony to know how to do it easily...

The propagation has been added since commit 4a698da (https://github.com/odoo/odoo/commit/4a698da) but in most case it should not be used to make sum, ... Qweb is for templating... 

Have a good day

JKE

Duplicated:

https://www.odoo.com/forum/help-1/question/how-to-pass-qweb-variable-values-within-html-elements-in-a-loop-71675

https://www.odoo.com/forum/help-1/question/qweb-loop-cannot-set-value-to-vaiables-outside-the-loop-71486

https://www.odoo.com/forum/help-1/question/qweb-get-variable-value-from-loop-74531

https://github.com/odoo/odoo/issues/4461