example of query completion

Hi,

I am working on a simple desktop environment
http://www.logilab.org/project/simpled

I am trying to get completion to work when querying for user input in
the ion command bar. 

I read the documentation at
http://modeemi.fi/~tuomov/ion-doc-3/ionconf/node7.html#SECTION00730000000000000000
I looked for examples on the web, I tried to reuse code from the
ion3-scripts (as in
http://modeemi.fi/~tuomov/repos/ion-scripts-3/scripts/query_url.lua).

So far I had no success. The API changed recently and the scripts are
not working any more. The doc does not provide a working example.

Could anyone give me an example of a completion setup similar to the
one from the query_url script ?

Thanks in advance,

-- 
Nicolas