Forum: Radiant CMS Backdoor and a problem in <r:find url=

I'm trying to get a a Link of some pages by url

<r:find url="=SOME_URL">
  <r:link />
</r:find>

Well, I'm using BackDoor Ext. to get the slug from other page i save
in.

<r:archive:children:each>
<r:ruby> @slug = "/shows/" + "<r:content part='Show' />"; "" </r:ruby>

<r:find url="=(@slug)">
  <r:link />
</r:find>
</r:archive:children:each>

it returns the the link of the same page.
while if I put <r:ruby> @slug </r:ruby> to check @slug value at each
loop it different from each other, like what I want!!