Hi,
our department is currently thinking about upgrading to Vaadin 7 for enabling SASS-Support for our new Web-Applications. Unfortunately i couldn’t find any information, which functionality of SASS has already been integrated.
Especially information about the current integration-status of the following sass-functionalities would be important:
Thanks alot in advance!
The current status in Vaadin 7.1 as far as I can tell:
For interpolation there is limited support - it works in some contexts but not everywhere.
Normal @extend should work. However, some special features like placeholder selectors for @extend-only and !optional might not be supported at the moment.
Basic list operations (at least append(), remove() and contains()) have been implemented, as have @if and @each, but there might be some limitations in their support and they haven’t been extensively tested. The other control functions (@for and @while) have not been implemented yet.
If I remember correctly, there are cases where some operations cannot be performed directly within the @if condition but as a workaround assigning the operation result to a variable and using it in @if should work.
Thank you very much. We’re gonna give it a shot 
I hope it works for you.
I’m currently in the process of implementing @function (custom functions), @return, @for, and @while on this ticket:
http://dev.vaadin.com/ticket/11776
(no code contributed yet, but I expect some to be contributed somewhat soon)