how to use an included document's key?

[ken tashiro]

Hi,

I have a question. Suppose documents are
[
{ "_id": "11111" },
{ "_id": "22222", "ancestors": ["11111"], "value": "hello" },
{ "_id": "33333", "ancestors": ["22222","11111"], "value": "world" }
]
like
http://wiki.apache.org/couchdb/Introduction_to_CouchDB_views#Linked_documents
and "include_docs=true".

I want to make a map function like
function(doc) {
    if (doc.ancestors) {
      for (var i in doc.ancestors) {
        if ( doc.value === 'world' AND ' value of ancestor is "hello" '  ) {
          emit (doc._id,ancestor's id);
        }
      }
    }
}
and get {"key":"33333",value:"22222"}.

My question is how can I use an  included document and know
 "value of ancestor" ?

Thank you.

ken tashiro